Evaluation of total lipids using enzymatic methods for the normalization of persistent organic pollutant levels in serum

Impact of high Spirulina diet, extruded or supplemented with enzymes, on blood cells, systemic metabolites, and hepatic lipid and mineral profiles of broiler chickens

The impact of 15% dietary inclusion of Spirulina (Arthrospira platensis) in broiler chickens was explored, focusing on blood cellular components, systemic metabolites and hepatic lipid and mineral composition. From days 14 to 35 of age, 120 broiler chickens were divided and allocated into four dietary treatments: a standard corn and soybean meal-based diet (control), a 15% Spirulina diet, a 15% extruded Spirulina diet, and a 15% Spirulina diet super-dosed with an enzyme blend (0.20% porcine pancreatin plus 0.01% lysozyme). The haematological analysis revealed no significant deviations (p > 0.05) in blood cell counts across treatments, suggesting that high Spirulina inclusion maintains haematological balance. The systemic metabolic assessment indicated an enhanced antioxidant capacity in birds on Spirulina diets (p < 0.001), pointing toward a potential reduction in oxidative stress. However, the study noted a detrimental impact on growth performance metrics, such as final body weight and feed conversion ratio (both p < 0.001), in the Spirulina-fed treatments, with the super-dosed enzyme blend supplementation failing to alleviate these effects but with extrusion mitigating them. Regarding hepatic composition, birds on extruded Spirulina and enzyme-supplemented diets showed a notable increase in n-3 fatty acids (EPA, DPA, DHA) (p < 0.001), leading to an improved n-6/n-3 PUFA ratio (p < 0.001). Despite this positive shift, a reduction in total hepatic lipids (p = 0.003) was observed without a significant change in cholesterol levels. Our findings underscore the need for further exploration into the optimal inclusion levels, processing methods and potential enzymatic enhancements of Spirulina in broiler diets. Ultimately, this research aims to strike a balance between promoting health benefits and maintaining optimal growth performance in poultry nutrition.

Association of exposure to mixture of chemicals during pregnancy with cognitive abilities and fine motor function of children

Chemical exposures often occur in mixtures and exposures during pregnancy may lead to adverse effects on the fetal brain, potentially reducing lower cognitive abilities and fine motor function of the child. We investigated the association of motheŕs exposure to a mixture of chemicals during pregnancy (i.e., organochlorine compounds, per- and polyfluoroalkyl substances, phenols, phthalates, organophosphate pesticides) with cognitive abilties and fine motor function in their children. We studied 1097 mother-child pairs from five European cohorts participating in the Human Early Life Exposome study (HELIX). Measurement of 26 biomarkers of exposure to chemicals was performed on urine or blood samples of pregnant women (mean age 31 years). Cognitive abilities and fine motor function were assessed in their children (mean age 8 years) with a battery of computerized tests administered in person (Raveńs Coloured Progressive Matrices, Attention Network Test, N-back Test, Trail Making Test, Finger Tapping Test). We estimated the joint effect of prenatal exposure to chemicals on cognitive abilities and fine motor function using the quantile-based g-computation method, adjusting for sociodemographic characteristics. A quartile increase in all the chemicals in the overall mixture was associated with worse fine motor function, specifically lower scores in the Finger Tapping Test [-8.5 points, 95 % confidence interval (CI) -13.6 to -3.4; -14.5 points, 95 % CI -22.4 to -6.6, and -18.0 points, 95 % CI -28.6 to -7.4) for the second, third and fourth quartile of the overal mixture, respectively, when compared to the first quartile]. Organochlorine compounds, phthalates, and per- and polyfluoroalkyl substances contributed most to this association. We did not find a relationship with cognitive abilities. We conclude that exposure to chemical mixtures during pregnancy may influence neurodevelopment, impacting fine motor function of the offspring.

Circulating organochlorine pesticide levels, genetic predisposition and the risk of incident type 2 diabetes

Persistent organochlorine pesticide (OCP) has been associated with type 2 diabetes (T2D), and genetic polymorphism might modify such an association. However, prospective evidence remains scarce. We conducted a nested case-control study comprising 1006 incident diabetic cases and 1006 matched non-diabetic controls [sex and age (±5 years)] from 2008 to 2013 (mean follow-up period: ∼4.6 years) based on the Dongfeng-Tongji cohort in Shiyan City of China, determined baseline levels of nineteen OCPs, and examined the associations of circulating OCPs, both individually and collectively, with incident T2D risk. We also constructed overall genetic risk score (GRS) based on 161 T2D-associated variants and five pathway-specific cluster GRSs based on established variants derived from the Asian population. Compared with the first quartile of serum β-BHC levels, the multivariable-adjusted ORs (95% CIs) of incident T2D risk in the second, third, and fourth quartiles were 0.98 (0.70-1.39), 1.43 (0.99-2.07), and 1.75 (1.14-2.68), respectively (FDR-adjusted Ptrend = 0.03). A positive association was observed between serum OCP mixture and incident T2D risk and can be largely attributed to β-BHC. Furthermore, serum β-BHC and p,p'-DDE showed significant interactions with the GRS for lipodystrophy, a T2D-related pathway representing fat redistribution to viscera, on T2D risk (Pinteraction < 0.05). In conclusion, higher circulating OCP levels were independently associated with an increased risk of T2D, with β-BHC possibly being the major contributor. Genetic predisposition to T2D-related morbidity, such as visceral adiposity, should be considered when assessing the risk of T2D conferred by OCPs.

Exposure profiles in pregnant women from a birth cohort in a highly contaminated area of southern Italy

Protecting the health of pregnant women from environmental stressors is crucial for reducing the burden of non-communicable diseases. In industrially contaminated sites, this action is particularly challenging due to the heterogeneous pollutant mixtures in environmental matrices. The aim of this study was to evaluate distribution patterns of mercury, hexachlorobenzene and polychlorobiphenyls in the serum of 161 pregnant women recruited in the framework of the Neonatal Environment and Health Outcomes (NEHO) cohort and living both inside and outside the National Priority Contaminated Site (NPCS) of Priolo. Food macro-categories were determined, and serum levels of contaminants were used to perform k-means cluster analysis and identify the role of food in pollutant transfer from the environment. Two groups of mothers with high and low measured pollutant levels were distinguished. Concentrations in mothers in the high-exposure cluster were at least twofold for all the evaluated pollutants (p < 0.0001) and included mothers living inside and outside NPCS, with a predominance of individuals from the NPCS (p = 0.045). Fish consumption was higher in the high-exposure cluster (p = 0.019). These findings suggest a link between contamination of environmental matrices such as sediment with maternal exposure, through the intake of local food. Such consideration appears poorly investigated in the context of contaminated sites.

Concentrations and homologue patterns of SCCPs and MCCPs in the serum of the general population of adults in Hangzhou, China

Due to their ubiquitous presence in the environment and humans, chlorinated paraffins (CPs) are a major environmental and public health concern. CPs are known to persist, bioaccumulate and potentially threaten human health, but reports on their internal exposure in the adult general population are still scarce. In this study, serum samples collected from adults living in Hangzhou, China, were quantified for SCCPs and MCCPs using GC-NCI-MS methods. A total of 150 samples were collected and subjected to analysis. ∑SCCPs were detected in 98% of the samples with a median concentration of 721 ng/g lw. MCCPs were found in all serum samples with a median concentration of 2210 ng/g lw, indicating that MCCPs were the dominant homologous group. For SCCPs and MCCPs, ∑C₁₀ and ∑C₁₄ were found to be the dominant carbon chain length homologues. Our results showed that age, BMI and lifestyle were not found to be significantly associated with internal exposure to CPs for the samples in this study. Based on PCA analysis, an age-specific distribution of CP homologues was observed. This suggests that internal exposure to CPs in the general population is related to exposure scenarios and history. The results of this study may contribute to a better understanding of the internal exposure to CPs in the general population and may provide a direction for the investigation of the source of exposure to CPs in the environment and daily life.

Prenatal exposure to 209 PCBs in mother-infant pairs from two cities in China: Levels, congener profiles, and transplacental transfer

Prenatal exposure to polychlorinated biphenyls (PCBs) has been well researched, but studies covering all 209 congeners are limited. Recent literature suggests a shift in the dominant congeners and increasing levels of unintentionally-produced PCBs (UP-PCBs) in environmental samples in China. To investigate the exposure levels and profiles of PCBs in pregnant women and newborns, as well as the characteristics of transplacental transfer, we measured 209 PCBs in 80 pairs of maternal serum (MS) and cord serum (CS) from Hangzhou and Mianyang, China. The levels of ∑PCBs of participants in this study were lower than those in developed countries and followed the order of (ng/g lw): Hangzhou-MS (148) > Hangzhou-CS (107) > Mianyang-MS (63.8) > Mianyang-CS (57.9). UP-PCBs (mainly PCB-11) contributed around 50% of ∑PCBs in serum, which is consistent with the environmental samples. Environmental burden and dietary intake may account for the differences in the exposure levels, while the historical production and release may have impacted the homologue profiles. Prenatal exposure to PCB-126 was associated with increased birth weight (n = 80, adjusted β = 0.270, p = 0.030). The body burden of dioxin-like PCBs of newborns in Hangzhou was 82.4 pg TEQ/kg bw, suggesting certain health risks under WHO tolerable daily intake of 1-4 pg TEQ/kg bw. Log₁₀ K_OW was negatively correlated with log₁₀-transformed transplacental transfer efficiency (R² = 0.36, p < 0.001), serving its importance for PCBs' transplacental transfer. This study is the first to investigate maternal and fetal exposure to PCBs in China based on their levels, congener and homologue profiles, and potential adverse effects. Our findings help to provide insights into the processes and factors influencing the transplacental transfer of PCBs.

Dietary Ulva lactuca and CAZyme supplementation improve serum biochemical profile and hepatic composition of weaned piglets

Ulva lactuca is a seaweed with antinutritional cell wall for monogastrics. Carbohydrate-Active enZymes (CAZymes) supplementation can potentially cause its disruption. This study evaluates four diets: Ctrl-control diet; UL-control + 7% U. lactuca (wild caught, powdered form); ULR-UL + 0.005% Rovabio^® Excel AP; ULU-UL + 0.01% ulvan lyase on piglets' haematologic and serologic profiles, hepatic lipids and minerals. White blood cells and lymphocytes reached the highest values in piglets fed UL compared to control, and to control and ULR; respectively (P < 0.05). IgG levels were boosted by seaweed incorporation compared to control (P = 0.015). The glycaemic homeostasis was assured by the seaweed inclusion. Dietary seaweed decreased serum lipids (P < 0.001), with the exception of ULU, due to HDL-cholesterol increase (P < 0.001). Cortisol was decreased in ULR and ULU (P < 0.001). No systemic inflammation was observed (P > 0.05). While hepatic n-3 PUFA increased in piglets fed with seaweed diets due to increment of beneficial 22:5n-3 and 22:6n-3 fatty acids (P < 0.05), the opposite occurred for n-6 PUFA, PUFA/SFA and n-6/n-3 ratios (P < 0.05). Hepatic pigments were unchanged (P > 0.05). ULR reduced α-tocopherol levels (P = 0.036) and increased serum potassium levels (P < 0.001) compared to control. Seaweed contributed to overcome piglets' weaning stress, with some benefits of including CAZyme supplementation.

Effect of Laminaria digitata dietary inclusion and CAZyme supplementation on blood cells, serum metabolites and hepatic lipids and minerals of weaned piglets

Seaweeds, such as Laminaria digitata, are a sustainable alternative to conventional feedstuffs for weaned piglet diets, improving their health and mitigating environmental impacts. L. digitata has a complex cell wall that can be difficult for monogastrics to digest. However, carbohydrate-active enzymes (CAZymes) such as Rovabio® Excel AP and alginate lyase can help break down these polysaccharides and render intracellular nutrients more accessible. This study aimed to evaluate the impact of 10% L. digitata feed inclusion and CAZyme supplementation on piglet blood cells, serum metabolites, liver lipid and mineral profiles. Forty weaned piglets were randomly assigned to one of four diets (n = 10 each): a control diet, 10% L. digitata (LA), 10% L. digitata + 0.005% Rovabio® Excel AP (LAR), and 10% L. digitata + 0.01% alginate lyase (LAL). After two weeks of trial, animals were slaughtered and liver and blood serum samples taken for analysis. The results showed that the LA and LAL diets increased blood lymphocytes, IgG and IgM, and decreased serum lipids, improving both cellular and humoral immune response and cardiovascular health. Dietary CAZymes reversed the anti-inflammatory and hematopoietic effects. Additionally, cortisol levels were reduced with seaweed inclusion compared to the control diet (P < 0.001). In the liver, total n-3 PUFA and n-6/n-3 ratio were increased and decreased, respectively, due to eicosapentaenoic acid and α-linolenic acid accumulation (P < 0.001). However, total liver mineral content was incorporated to a lesser extent with the combined seaweed and enzyme diets (P < 0.001), potentially indicating a negative effect on mineral bioavailability. Overall, results suggest that a 10% L. digitata inclusion can effectively improve piglet health by reducing stress during weaning, without the need for dietary CAZymes.

Contamination Status of Pet Cats in Thailand with Organohalogen Compounds (OHCs) and Their Hydroxylated and Methoxylated Derivatives and Estimation of Sources of Exposure to These Contaminants

In this study, we analyzed serum samples of pet cats from Thailand and estimated the contribution to organohalogen compounds (OHCs) exposure through cat food and house dust intake. BDE-209 was predominant in cat sera and accounted for 76% of all polybrominated diphenyl ethers (PBDEs). Decabromodiphenyl ether (BDE-209) is a major contaminant in dry cat food and house dust, which has been estimated to be a source of exposure for Thai pet cats. BDE-209 is a major contaminant of OHCs in dry cat food and house dust, which was estimated to be a source of exposure for Thai pet cats. On the other hand, the level of contamination by PCBs was lower than in other countries. Analysis of pet foods suggested that BDE-209 in pet cat serum was attributable to the consumption of dry cat food. On the other hand, house dust also contained high concentrations of BDE-209. Thus, high levels of BDE-209 in pet cat sera can be attributed to the consumption of dry cat food and house dust. These results suggest that pet cats are routinely exposed to non-negligible levels of OHCs.

The Lipid Profile and Biochemical Parameters of COPD Patients in Relation to Smoking Status

Tobacco consumption is the most incriminated and studied risk factor for Chronic obstructive pulmonary disease (COPD), but other factors such as air pollution, are also linked to this disease. One of the known aspects of this chronic lung disease is that its occurrence is mainly due to the chronic inflammation of the airways. Lipid metabolism seems to be affected by smoking, with studies showing a correlation between this habit and high levels of triglycerides and low levels of high-density lipoprotein cholesterol (HDL-CHOL). Uric acid concentration is thought to reflect the antioxidative capacity of the body because it is the most abundant aqueous antioxidant. The aim of this study was to investigate the lipid profile and biochemical parameters of COPD patients in relation to smoking status. The present study was conducted between 2020 and 2021 in the Clinical Hospital of Pneumology in Iasi, Romania. Patients diagnosed with COPD (n = 52) were included and divided in three groups depending on their smoking status: non-smokers, smokers and ex-smokers. The obtained results show low correlations between COPD stages and serum uric acid concentrations (r = 0.4; p ˂ 0.05), smoking status (smoker/non-smoker/ex-smoker) and total serum cholesterol values (r = 0.45; p ˂ 0.05), but also between serum urea concentrations and the number of packs-years for the smoker/ex-smoker groups (r = 0.45, p ˂ 0.05). Smoking was associated with changes in the lipid profile of smokers and ex-smokers, along with increased low-density lipoprotein cholesterol (LDL-CHOL) and low serum uric acid values.

Plasma Metabolites and Liver Composition of Broilers in Response to Dietary Ulva lactuca with Ulvan Lyase or a Commercial Enzyme Mixture

The effect of a high incorporation level of Ulva lactuca, individually and supplemented with a Carbohydrate-Active enZyme (CAZyme) on broilers’ plasma parameters and liver composition is assessed here. Twenty one-day-old Ross 308 male broilers were randomly assigned to one of four treatments (n = 10): corn/soybean meal based-diet (Control); based-diet with 15% U. lactuca (UL); UL diet with 0.005% of commercial carbohydrase mixture; and UL diet with 0.01% of recombinant ulvan lyase. Supplementing U. lactuca with the recombinant CAZyme slightly compromised broilers’ growth by negatively affecting final body weight and average daily gain. The combination of U. lactuca with ulvan lyase also increased systemic lipemia through an increase in total lipids, triacylglycerols and VLDL-cholesterol (p < 0.001). Moreover, U. lactuca, regardless of the CAZyme supplementation, enhanced hepatic n-3 PUFA (mostly 20:5n-3) with positive decrease in n-6/n-3 ratio. However, broilers fed with U. lactuca with ulvan lyase reduced hepatic α- and γ-tocopherol concentrations relative to the control. Conversely, the high amount of pigments in macroalga diets led to an increase in hepatic β-carotene, chlorophylls and total carotenoids. Furthermore, U. lactuca, alone or combined with CAZymes, enhanced hepatic total microminerals, including iron and manganese. Overall, plasma metabolites and liver composition changed favorably in broilers that were fed 15% of U. lactuca, regardless of enzyme supplementation.

Associations between Maternal Polychlorinated Dibenzo-p-dioxin and Dibenzofuran Serum Concentrations and Pulse Pressure in Early Pregnancy: A Cross-Sectional Study

Pulse pressure (PP) is the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP), and an independent predictor of cardiovascular risk. Previous research suggests, with different conclusions, that exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) could affect blood pressure (BP). We conducted a cross-sectional study to determine the association of dioxin exposure with PP in early pregnancy. A total of 305 pregnant women in early pregnancy in Yingcheng, China, recruited from May 2018 to February 2021, were included in this study. We measured 17 congeners of PCDD/Fs in maternal serum via high-resolution gas chromatography tandem high-resolution mass spectrometry. A generalized linear regression model was used to analyze the influencing factors of dioxin exposure and their relationships with PP. The levels of total PCDD/Fs (∑PCDD/Fs) ranged from 163.52 pg/g lipid to 1,513,949.52 pg/g lipid, with a mean of 10,474.22 pg/g lipid. The mean toxicity equivalent (TEQ) of total PCDD/Fs (∑TEQ-PCDD/Fs) was 42.03 pg/g lipid. The ratio of tetrachlorinated to octa-chlorinated congeners in maternal serum was enriched with an increasing number of chlorines. Pregnant women with college and above education had higher concentrations of ∑PCDD/Fs than those with education levels of junior high school and below (β = 0.34, 95% CI: 0.01, 0.67). The adjusted model for ∑TEQ-PCDD/Fs was significantly and negatively associated with PP (β = -1.79, 95% CI: -2.91, -0.68). High levels of dioxins were found in this area, and exposure to dioxins may affect the PP of women in early pregnancy, with health risks.

Impact of dietary Chlorella vulgaris and feed enzymes on health status, immune response and liver metabolites in weaned piglets

In this study, we analysed the impact of dietary inclusion of Chlorella vulgaris and carbohydrases on general health, redox status, immune response, liver lipids and metabolites in weaned piglets. Forty-four male piglets were allocated into four diets: control (n = 11), CH (control diet with 5% CH, n = 10), CH+R (control diet with 5% CH plus 0.005% Rovabio Excel AP, n = 10), and CH+M (control diet with 5% CH plus 0.01% of a pre-selected four-CAZyme mixture, n = 11). After 15 days of trial, animals were slaughtered and samples of blood and liver collected. Spectrophotometry methods and commercial kits were used to determine blood parameters and gas and liquid chromatography for hepatic fatty acid and chlorophylls profiles, respectively. While total, LDL- and VLDL-cholesterol were increased by CH, the opposite was recorded for HDL-cholesterol (p < 0.001). Piglets fed CH-based diets presented an increase of IgG and a decrease of IgM (p < 0.001) which along with lymphocytes exacerbation contributed for piglets' survival after weaning. n-6 PUFA were reduced in piglets fed CH and the opposite occurred for n-3 PUFA (p < 0.001), thus benefiting n-6/n-3 ratio in the liver. Chlorophylls amount was not changed by the use of Rovabio or enzymatic mixture. The discriminant analysis applied to hepatic parameters revealed a clear separation between control and CH-based diets but failed to discriminate feed enzymes. Our findings indicate health promoting effects of CH as feed ingredient in piglets' nutrition at weaning, without negatively impacting on animals' performance.

Antioxidant enzyme activity and pathophysiological responses in the freshwater walking catfish, Clarias batrachus Linn under sub-chronic and chronic exposures to the neonicotinoid, Thiamethoxam®

The hydrophilic nature and resultant persistence of neonicotinoids in aquatic systems increase the exposure duration for non-target organisms. The sublethal toxicity of the neonicotinoid Thiamethoxam® spanning sub-chronic and chronic durations was investigated in Clarias batrachus, a non-target freshwater fish species. 96 h LC₅₀ value of Thiamethoxam® on Clarias batrachus was 138.60 mg L^-1. Pre-determined exposure concentrations of Thiamethoxam® (6.93 and 13.86 mg L^-1) were used and effects were assessed at days 15, 30, and 45 exposure intervals. Biomarker effects were evaluated using antioxidant enzyme responses (CAT, SOD) neurotransmission (acetylcholinesterase activity), haematological and serum biochemistry changes (including haemoglobin content, total erythrocyte count, and serum albumin total leukocyte count, total serum protein, serum globulin, triglyceride, cholesterol, high-density lipoprotein, very low-density lipoprotein, low-density lipoprotein, phospholipid, and total serum glucose), histopathological alterations (gill and liver). Thiamethoxam®-exposed fish showed a marked reduction in haemoglobin content, total erythrocyte count, and serum albumin levels compared to control fish. Similarly, gill and liver antioxidant enzyme activity (CAT, SOD) and neurotransmission (acetylcholinesterase) also showed altered responses between sub-chronic exposure on day-15 and chronic responses on day-45. Histopathological observations in gill tissue revealed alterations ranging from vacuolation, hypertrophy, disruption of primary lamellar architecture, haemorrhage, the fusion of secondary lamella, and sloughing of outer epithelia. For liver tissue of exposed fish histopathological observations included increased sinusoidal spaces (ISS), necrosis of hepatocytes (NOH), nuclear degeneration (ND), disruption of architecture (DOA), macrophage infiltration of the central vein, vacuolation (V), hypertrophied hepatocytes, and haemorrhages. The gradients of toxic responses across exposure concentrations and depictions of impaired fish health with increasing thiamethoxam® exposure duration portend lowered physiological capacity for survival in the wild.

Human biomonitoring of persistent and non-persistent pollutants in a representative sample of the general population from Cape Verde: Results from the PERVEMAC-II study

International Public Health authorities recommend biomonitoring studies to assess the exposure to chemicals in the general population. The aim of the present study was to analyze the blood concentrations of a total 360 pollutants, including 230 pesticides in current or recent use, 59 persistent organochlorine pollutants (POPs), 11 anticoagulant rodenticides and 60 pharmaceutical active compounds (PhACs), in a cohort of 403 subjects from Cape Verde. The study was performed in the frame of the Pesticide Residues in Vegetables of the Macaronesia project (PERVEMAC-II). A total of 60 out of 360 toxic compounds (16.7%) were detected, at least, in one participant. The three most frequently detected substances were p,p'-DDE (100%), phenanthrene (94.0%) and hexachlobenzene (35.9%). 2-Phenylphenol and imidacloprid were detected in 29.0 and 14.4% of the population. The three substances with the highest serum concentrations were PhACs: naproxen (249.1 ng/mL), metronidazole (115.6 ng/mL) and acetaminophen (25.2 ng/mL). Median blood concentration of p,p'-DDE, HCB and phenanthrene were 1.87, 0.08 and 0.36 ng/mL. Blood concentrations of POPs were influenced by age, although both gender and body mass index may exert an influence in the presence of these substances. Lifestyle has an effect on the concentration of these substances, especially in terms of dietary habits. Both the frequency of detection and the concentration of the studied substances are similar to those of other biomonitored populations. This is the first biomonitoring study carried out in Cape Verde. Our results may be useful for the implementation of public health measures by the competent authorities.

Enzymological, histological, and serum biomarker responses of snubnose pompano on complete replacement of fishmeal using cottonseed meal supplemented with lysine and methionine in the diet

In a feeding experiment, cottonseed meal (CSM) was used to replace fishmeal (FM) in the diet of snubnose pompano, Trachinotus blochii, supplemented with lysine and methionine to assess the growth, nutritive profile, hematological, histological, and stress biomarker response. Experimental fishes were randomly stocked in five treatments each with triplicates. Five isonitrogenous and isolipidic diets with graded level of CSM (0, 8.7, 17.4, 26.0, and 34.7%) as replacement for FM protein (0, 25, 50, 75, and 100%) were formulated and fed to respective treatments. Comparison between various parameters among the treatments was made using orthogonal polynomial contrasts to indicate the statistical significance. Higher alkaline phosphatase, acid phosphatase, lactate dehydrogenase, malate dehydrogenase, aspartate, and alanine aminotransferase activities were observed in 0CSM group and followed by 100CSM group as higher inclusion level of CSM with higher free gossypol content did not affect the metabolic enzyme activities. The maximum muscular free gossypol accretion of 1.28 mg kg^-1 (on wet basis) was recorded in 100CSM group which was very well below the critical limit set by FDA. As a conclusion, fishmeal can be completely replaced using cottonseed meal in the diet of pompano without adverse effect on growth, metabolism, and general health.

Combined effects of dietary Laminaria digitata with alginate lyase on plasma metabolites and hepatic lipid, pigment and mineral composition of broilers

BACKGROUND

The Laminaria digitata is an abundant macroalga and a sustainable feedstock for poultry nutrition. L. digitata is a good source of essential amino acids, carbohydrates and vitamins, including A, D, E, and K, as well as triacylglycerols and minerals, in particular iron and calcium. However, the few studies available in the literature with broilers document the application of this macroalga as a dietary supplement rather than a feed ingredient. No study has addressed up until now the effects of a high-level incorporation (> 2% in the diet) of L. digitata on plasma biochemical markers and hepatic lipid composition, as well as minerals and pigments profile in the liver of broilers. Our experimental design included one hundred and twenty Ross 308 male birds contained in 40 wired-floor cages and distributed to the following diets at 22 days of age (n = 10) for 15 days: 1) a corn-soybean basal diet (Control); 2) the basal diet plus 15% of L. digitata (LA); 3) the basal diet plus 15% of L. digitata with 0.005% of Rovabio® Excel AP (LAR); and 4) the basal diet plus 15% of L. digitata with 0.01% of the recombinant CAZyme, alginate lyase (LAE).

RESULTS

L. digitata compromised birds' growth performance by causing a reduction in final body weight. It was found an increase in hepatic n-3 and n-6 fatty acids, in particular C18:2n-6, C18:3n-6, C20:4n-6, C20:5n-3, C22:5n-3 and C22:6n-3 with the addition of the macroalga, with or without feed enzymes, to the broiler diets. Also, the beneficial C18:3n-3 fatty acid was increased by combining L. digitata and commercial Rovabio® Excel AP compared to the control diet. The sum of SFA, MUFA and the n-6/n-3 PUFA ratio were decreased by L. digitata, regardless the addition of exogenous enzymes. β-carotene was enhanced by L. digitata, individually or combined with CAZymes, being also responsible for a positive increase in total pigments. Macrominerals, in particular phosphorous and sulphur, were increased in the liver of broilers fed L. digitata individually relative to the control. For microminerals, copper, iron and the correspondent sum were consistently elevated in the liver of broilers fed L. digitata, individually or combined with exogenous CAZymes. The powerful discriminant analysis tool based on the hepatic characterization revealed a good separation between the control group and L. digitata diets but failed to discriminate the addition of feed enzymes.

CONCLUSIONS

Overall, this study highlights the value of L. digitata as a feed ingredient for the poultry industry. Moreover, we can conclude that the effect of L. digitata overpowers the effect of feed enzymes, both the Rovabio® Excel AP and the alginate lyase. Having in mind the negative effects observed on birds' performance, our main recommendation at this stage is to restraint L. digitata incorporation level in forthcoming nutritional studies.

Sex differences in the association of measures of sexual maturation to common toxicants: Lead, dichloro-diphenyl-trichloroethane (DDT), dichloro-diphenyl-dichloroethylene (DDE), and polychlorinated biphenyls (PCBs)

Many studies of human toxicant exposure examine the hypothesis that human sexual maturation can be affected through endocrine disruption. Within this body of literature there is significant variation in the findings. Variation may be related to the differential effects by toxicants between males and females as well as variation in sample size, toxicant levels, and the timing of exposure. We review sexual maturation outcomes between males and females when exposed to lead, dichlorodiphenyldichloroethylene (DDE), dichloro-diphenyl-trichloroethane (DDT), and polychlorinated biphenyls (PCBs) using a systematic process to gather peer-reviewed studies published from January 1994 through December 2019 on the NCBI website's PubMed search engine. The review includes 34 studies, some comprised of multiple analyses, to compare effects on sexual maturation by sex. The analysis shows that both boys and girls have delayed sexual maturation in relation to lead exposure. There are differences in the direction of effects associated with DDE/DDT and PCB exposure in boys and girls. PCBs exist as congeners of many structural forms, and that variation is considered in this review. Dioxin-like and non-dioxin-like PCBs exposure directionality differed between boys and girls as well. Future investigations into the basis of sex variation in DDE/DDT and PCB relationships to sexual maturation are warranted.

Prenatal exposure to polycyclic aromatic hydrocarbons and effects on neonatal anthropometric indices and thyroid-stimulating hormone in a Middle Eastern population

Prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) evokes extensive concerns regarding public health. Monitoring the pregnant women's exposure can be considered a suitable alternative to assess the fetus's exposure. This study aimed to monitor pregnant women's exposure (n = 126) to PAHs using a biomonitoring approach to evaluate effects on anthropometric indices and neonatal thyroid-stimulating hormone (TSH) in Shiraz, Iran. PAHs priority compounds were measured by gas chromatography-mass spectrometry (GC-MS) after separating blood serum and liquid-liquid extraction (LLE) method. Information on anthropometric indices, neonatal TSH levels, and data from the respondents was obtained from medical records and questionnaires. The mean PAHs concentrations ranged from 0.29 to 327.91 ng/g lipid. There was no significant difference between the measured PAHs in maternal serum at the seventh month and pregnancy termination except for ACY (p-Value<0.05). Regression analysis results showed a significant correlation (p-value<0.05) between exposure to passive smoke and total PAHs concentrations. There was no significant relationship between exposure to PAHs and weight, height, head circumference, and Apgar score of newborns. The results showed TSH decreased by 0.99 units as ACE increased per unit (β = -0.001). This study is the first to evaluate relationships between prenatal exposure to PAHs and effects on newborn health indicators, including TSH levels in a Middle Eastern population. Future studies are suggested to perform detailed assessments of PAHs intake sources, especially in vulnerable populations such as pregnant women and children.

Biomonitoring of 89 POPs in blood serum samples of Czech city policemen

In this biomonitoring study, we evaluated the concentrations of 8 polychlorinated biphenyls (PCBs), 11 organochlorinated pesticides (OCPs), 33 brominated flame retardants (BFRs), 7 novel brominated and chlorinated flame retardants (novel FRs) and 30 per- and polyfluoroalkylated substances (PFAS) in human serum samples (n = 274). A total of 89 persistent organic pollutants (POPs) were measured in blood serum samples of city policemen living in three large cities and their adjacent areas (Ostrava, Prague, and Ceske Budejovice) in the Czech Republic. All samples were collected during the year 2019 in two sampling periods (spring and autumn). The identification/quantification of PCBs, OCPs, BFRs, novel FRs and PFAS was performed by means of gas chromatography coupled to (tandem) mass spectrometry (GC-MS/(MS)) and ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-MS/MS). The most frequently detected pollutants were perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHxS), 2,2',3,4,4',5'-hexachlorobiphenyl (CB 138), 2,2',4,4',5,5'-hexachlorobiphenyl (CB 153), 2,2',3,3',4,4',5-heptachlorobiphenyl (CB 170), 2,2',3,4,4',5,5'-heptachlorobiphenyl (CB 180), hexachlorobenzene (HCB), and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) quantified in 100% of serum samples. In the serum samples, the concentrations of determined POPs were in the range of 0.108-900 ng g^-1 lipid weight (lw) for PCBs, 0.106-1016 ng g^-1 lw for OCPs, <0.1-618 ng g^-1 lw for FRs and <0.01-18.3 ng mL^-1 for PFAS, respectively. Locality, sampling season, and age were significantly associated with several POP concentrations. One of the important conclusions was that within the spring sampling period, statistically significant higher concentrations of CB 170 and CB 180 were observed in the samples from Ostrava (industrial area) compared to Prague and Ceske Budejovice. Older policemen had higher concentrations of five PCBs and two OCPs in blood serum.

Short- and medium-chain chlorinated paraffins in human blood serum of Czech population

Short- and medium-chain chlorinated paraffins (SCCPs; MCCPs) are widespread environmental pollutants with bioaccumulation potential and adverse effects on human health. The analysis of blood serum is an important strategy to assess the human exposure to various contaminants, including SCCPs and MCCPs. Lately, the information about the exposure of Chinese population has been reported; nevertheless, data on human exposure to SCCPs and MCCPs outside East Asia are still very limited. In this pilot study, SCCPs and MCCPs were determined in 27 serum samples obtained from Czech adults. The samples were extracted by a three-step extraction (repeated with a clean solvent) by a mixture of n-hexane:diethyl ether (9:1, v/v) with subsequent clean-up on Florisil® solid phase extraction column. Gas chromatography coupled with high resolution mass spectrometry operated in negative chemical ionisation was employed for the instrumental analysis. The method recoveries ranged from 71 to 89% with repeatabilities of <20% (expressed as relative standard deviation). In the samples, SCCP concentrations were in the range of <150-2600 ng/g lipid weight, lw (median 370 ng/g lw) and the MCCP concentrations were in the range of <200-2110 ng/g lw (median 360 ng/g lw), respectively. To the best of our knowledge, our reported results are the first data about chlorinated paraffins in human blood serum in Europe, showing exposure to these compounds with yet to be studied effects on human health.

Assessment of Exposure of Korean Firefighters to Polybrominated Diphenyl Ethers and Polycyclic Aromatic Hydrocarbons via Their Measurement in Serum and Polycyclic Aromatic Hydrocarbon Metabolites in Urine

This study investigated the occupational exposure of Korean firefighters to a suite of combustion-related pollutants. Exposure to polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) was assessed by measurement of their levels in serum and metabolites in urine (i.e., monohydroxylated PAHs, OH-PAHs). The mean level of ∑PBDEs in the serum of firefighters (17.1 ng/g lipid weight (lw)) was significantly higher than that of the general population (1.39 ng/g lw) (Mann-Whitney U Test, p < 0.05), which is similar to the ∑PAH levels (1286 ng/g lw for firefighters and 1016 ng/g lw for the general population). Individual OH-PAH levels showed 2.1- to 4.2-fold increases in postfire urine samples compared to the control urine samples, with the mean ∑OH-PAHs being significantly higher in postfire urine samples (22,658 ng/g creatinine) than in the control urine samples (10,253 ng/g creatinine) (Mann-Whitney U test, p < 0.05). It was found that ∑PBDEs correlated with firefighters' length of service and years dedicated to on-site dispatch, while ∑OH-PAHs was strongly associated with firefighters' exposure duration, age, length of service, and years dedicated to on-site dispatch. Indeed, the results of the present study indicate that Korean firefighters are prone to elevated risk of exposure to toxic combustion-related pollutants compared with the general population.

Per- and polyfluoroalkyl substances (PFASs) in Swedish household dust and exposure of pet cats

Per- and polyfluoroalkyl substances (PFASs) are used in a wide range of products and have been found ubiquitously in our indoor environment, and there is evidence that exposure to PFAS can lead to adverse endocrine effects, such as thyroid hormone disruption. Pet cats have a high dust intake due to their grooming behavior and have been shown to be a suitable sentinel species for assessment of toddler's exposure. Here we used paired household dust (n=46) and cat serum (n=27) samples to establish whether dust is a relevant exposure pathway to PFASs. An analytical method for PFAS analysis was optimized using a low volume of cat serum samples, combining solid-phase extraction and online sample cleanup. Dust was extracted with methanol by sonication and cleaned up by addition of active carbon. In total, 27 PFASs were analyzed by liquid chromatography/mass spectrometry analysis. The correlation between PFAS levels in dust and serum, serum lipids and thyroid hormone levels, and PFAS levels in dust between different rooms were statistically evaluated. PFOS and PFDA could be quantified in all cat serum samples (median 2300 pg/mL and 430 pg/mL, respectively), followed by PFOA (median 1100 pg/mL), quantified in 96% of the samples. The levels of 6:2 and 8:2 diPAPs were determined in 65% and 92% of the serum samples, respectively, and were an order of magnitude lower (1.4-160 pg/mL). Household dust on the other hand was dominated by 6:2 and 8:2 diPAPs, with a median of 65 ng/g dust and 49 ng/g dust, respectively. PFOS (median 13 ng/g dust) and PFOA (median 9 ng/g dust) were quantified in 93% of the dust samples. Only eight PFASs were detected (>LOD) in at least 50% of the samples of both matrices and could be paired. Significant correlations between cat serum and dust were found for PFOA (rS=0.32, p<0.049) and PFUnDA (rS=0.55, p<0.001). Significant positive correlations were found between serum total thyroxine (rS=0.11, p<0.05) and PFNA and between serum cholesterol and PFHpA (rS=0.46, p<0.01), PFUnDA (rS=0.40, p<0.05), PFDoDA (rS=0.44, p<0.01), and sum PFAS (rS=0.48, p<0.01). In conclusion, this study confirmed that dust is a relevant exposure pathway for the ingestion of some PFASs for cats, and the serum levels of PFASs could be of relevance for the cat's health.

Comparison of lipid-normalised concentrations of persistent organic pollutants (POPs) between serum and adipose tissue

Human biomonitoring of persistent organic pollutants (POPs) is typically based on serum analysis and for comparison and modelling purposes, data are often normalised to the lipid content of the serum. Such approach assumes a steady state of the compound between the serum lipids and for example lipid-rich adipose tissue. Few published data are available to assess the validity of this assumption. The aim of this study was to measure concentrations of POPs in both serum and adipose tissue samples from 32 volunteers and compare the lipid-normalised concentrations between serum and adipose tissue. For p,p'-DDE, PCB-138, PCB-153 and PCB-180, lipid-normalised adipose tissue concentrations were positively correlated to the respective serum concentrations but generally were more highly concentrated in adipose tissue. These results suggest that the investigated legacy POPs that were consistently found in paired samples may often not be in a steady state between the lipid compartments of the human body. Consequently, the analysis of serum lipids as a surrogate for adipose tissue exposure may more often than not underestimate total body burden of POPs. Further research is warranted to confirm the findings of this study.

Impact of dietary Chlorella vulgaris and carbohydrate-active enzymes incorporation on plasma metabolites and liver lipid composition of broilers

BACKGROUND

Chlorella vulgaris has been proposed as a sustainable green feedstock in poultry nutrition due to its ease of cultivation, minimal environmental impact and balanced nutritional composition. However, the majority of studies documents the use of C. vulgaris as a dietary supplement in broilers instead of a feed ingredient. To the best of our knowledge, no report has shown the effect of a high-level incorporation (>2 % in the diet) of C. vulgaris on plasma metabolites and hepatic lipid composition of broilers. One hundred and twenty Ross 308 male birds were housed in 40 wired-floor cages and randomly distributed by the following experimental diets at 22 days of age (n = 10) during 15 days: (1) a corn-soybean meal based diet (control); (2) based diet with 10% of C. vulgaris; (3) diet 2 supplemented with 0.005% Rovabio® Excel AP; and (4) diet 2 supplemented with 0.01% of a pre-selected four-CAZyme mixture.

RESULTS

The inclusion of C. vulgaris at 10% in the diet, regardless of the presence of exogenous CAZymes, changed plasma metabolites but did not compromise broilers growth. Plasma total lipids increased in broilers fed C. vulgaris combined with the two feed CAZymes (p < 0.001) compared with the control diet. Moreover, the supplementation with Rovabio® increased total cholesterol and LDL-cholesterol, while the addition of the four-CAZyme mixture increased triacylglycerols, VLDL-cholesterol and ALP activity. In opposition, HDL-cholesterol levels decreased in broilers fed microalga alone (p = 0.002). Regarding hepatic composition, the inclusion of C. vulgaris in broiler diets, individually or combined with exogenous CAZymes, had a minor effect on fatty acids but improved the n-6/n-3 ratio and total carotenoids.

CONCLUSIONS

In summary, the inclusion of a high level (10%) of C. vulgaris in broiler´s diet, regardless of the presence of exogenous CAZymes, improved hepatic antioxidant composition and did not impair broiler's performance. In addition, the feed supplementation with CAZymes increased broilers lipemia. Therefore, dietary C. vulgaris at this incorporation level seems to be safe for animal health and do not compromise performance traits, with no need of CAZymes supplementation.

Human Biomonitoring Data Enables Evidence-Informed Policy to Reduce Internal Exposure to Persistent Organic Compounds: A Case Study

Human biomonitoring (HBM) monitors levels of environmental pollutants in human samples, which often is a topic of concern for residents near industrially contaminated sites (ICSs). Around an ICS area in Menen (Belgium), including a (former) municipal waste incinerator and a metal recovery plant, increasing environmental concentrations of dioxins and polychlorinated biphenyls (PCBs) were observed, causing growing concern among residents and authorities. The local community succeeded in convincing the responsible authorities to investigate the problem and offer research funding. Persistent organic pollutants (POPs) were measured in two consecutive HBM studies (2002-2006 and 2010-2011), in the context of the Flemish Environment and Health Study (FLEHS), as well as in soil and locally produced food. Meanwhile, local authorities discouraged consumption of locally produced food in a delineated area of higher exposure risk. Ultimately, HBM and environmental data enabled tailored dietary recommendations. This article demonstrates the usefulness of HBM in documenting the body burdens of residents near the ICS, identifying exposure routes, evaluating remediating actions and providing information for tailored policy strategies aiding to further exposure reduction. It also highlights the role of the local stakeholders as an example of community-based participatory research and how such an approach can create societal support for research and policy.

Neurodevelopmental toxicity assessment of flame retardants using a human DNT in vitro testing battery

Due to their neurodevelopmental toxicity, flame retardants (FRs) like polybrominated diphenyl ethers are banned from the market and replaced by alternative FRs, like organophosphorus FRs, that have mostly unknown toxicological profiles. To study their neurodevelopmental toxicity, we evaluated the hazard of several FRs including phased-out polybrominated FRs and organophosphorus FRs: 2,2′,4,4′-tetrabromodiphenylether (BDE-47), 2,2′,4,4′,5-pentabromodiphenylether (BDE-99), tetrabromobisphenol A, triphenyl phosphate, tris(2-butoxyethyl) phosphate and its metabolite bis-(2-butoxyethyl) phosphate, isodecyl diphenyl phosphate, triphenyl isopropylated phosphate, tricresyl phosphate, tris(1,3-dichloro-2-propyl) phosphate, tert-butylphenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, tris(1-chloroisopropyl) phosphate, and tris(2-chloroethyl) phosphate. Therefore, we used a human cell–based developmental neurotoxicity (DNT) in vitro battery covering a large variety of neurodevelopmental endpoints. Potency according to the respective most sensitive benchmark concentration (BMC) across the battery ranked from <1 μM (5 FRs), 1<10 μM (7 FRs) to the >10 μM range (3 FRs). Evaluation of the data with the ToxPi tool revealed a distinct ranking (a) than with the BMC and (b) compared to the ToxCast data, suggesting that DNT hazard of these FRs is not well predicted by ToxCast assays. Extrapolating the DNT in vitro battery BMCs to human FR exposure via breast milk suggests low risk for individual compounds. However, it raises a potential concern for real-life mixture exposure, especially when different compounds converge through diverse modes-of-action on common endpoints, like oligodendrocyte differentiation in this study. This case study using FRs suggests that human cell–based DNT in vitro battery is a promising approach for neurodevelopmental hazard assessment and compound prioritization in risk assessment.

Environmental exposure to organochlorine pesticides and its association with the risk of hearing loss in the Chinese adult population: A case-control study

Hearing loss is a common chronic sensory deficit that has become a major public health concern worldwide. Hearing loss is well documented to be induced by noise and ototoxic drugs, and the association of hearing loss with environmental pollutants has received increasing attention. Organochlorine pesticides (OCPs) are an important group of environmental pollutants that exist ubiquitously in the human body and continue to represent a significant environmental health concern. Our case-control study was performed to explore the association between serum levels of OCPs and the risk of hearing loss in China, including 87 case-control pairs. Serum concentrations of 15 OCPs were measured. Pearson's correlation analysis and principal component analysis of frequently detected (>80%) OCPs showed a different distribution pattern, indicating possible exposure sources/scenarios for the case-control adult population. A higher α-hexachlorocyclohexane (α-HCH) level was a risk factor for an increased prevalence of hearing loss. The risk of hearing loss was increased by approximately 5.25-fold in the highest tertile compared with the lowest tertile. Furthermore, a significant association of the α-HCH level with an increased hearing threshold was observed at mid/high frequencies. This study provided the first evidence indicating that exposure to α-HCH might be a potential risk factor for hearing loss.

Exploring reproductive associations of serum polybrominated diphenyl ether and hydroxylated brominated diphenyl ether concentrations among women undergoing in vitro fertilization

STUDY QUESTION

Are serum concentrations of polybrominated diphenyl ethers (PBDEs) and hydroxylated brominated diphenyl ethers (OH-BDEs) associated with IVF endpoints?

SUMMARY ANSWER

Positive associations were observed for BDE153 and several OH-BDEs with IVF endpoints.

WHAT IS KNOWN ALREADY

PBDEs have been voluntarily phased out of production in the USA and EU due to their persistence and toxicity to humans and ecosystems. PBDEs have been associated with implantation failure among women undergoing IVF, yet some animal studies suggest greater toxicity from their metabolites, OH-BDEs.

STUDY DESIGN, SIZE, DURATION

We evaluated a subset of 215 women (contributing 330 IVF cycles) enrolled between 2005 and 2016 in a longitudinal cohort based at Massachusetts General Hospital Fertility Center.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The following PBDEs were quantified: 47, 99, 100, 153 and 154 and the following OH-BDEs: 3-OH-BDE47, 5-OH-BDE47, 6-OH-BDE47 and 4-OH-BDE49. Clinical endpoints of IVF treatments were abstracted from electronic medical records. Associations of log-transformed PBDEs and OH-BDEs with IVF outcomes were assessed using multivariable generalized mixed models and cluster weighted generalized estimating equation models adjusted for lipids, age, BMI, race, year of sample collection, IVF protocol and FSH levels. Outcomes were adjusted to represent a percent change in outcome with an increase equal to the magnitude of the difference between the 75th and 25th percentiles for each specific compound (interquartile range (IQR) increase).

MAIN RESULTS AND THE ROLE OF CHANCE

Detection frequencies were highest for congeners 47 and 153 (82% ≥ method detection limit (MDL)) and metabolites 3 and 5-OH-BDE47 and 4-OH-BDE49 (92% > MDL). PBDE and OH-BDE geometric mean concentrations declined by up to 80% between participants recruited in 2005 and those recruited in 2016. An IQR increase of BDE153 was associated with an increase in the probability of implantation (relative risk (RR) = 1.26, 95% CI: 1.16, 1.36), clinical pregnancy (RR = 1.32, 95% CI: 1.19, 1.46) and live birth (RR = 1.34; 95% CI: 1.15, 1.54). An IQR increase in 3 and 5-OH-BDE47 was associated with increased probabilities of implantation (RR = 1.52; 95% CI: 1.11, 2.09), clinical pregnancy (RR = 1.66; 95% CI: 1.17, 2.36), and live birth (RR = 1.61; 95% CI: 1.07, 2.40). When models were stratified by race (White (86%)/Other race (14%)), associations remained positive for White women, yet inverse associations were observed for Other race women. An IQR increase in BDE47 was associated with a 46% decreased probability of clinical pregnancy (95% CI: 0.31, 0.95) for Other race women.

LIMITATIONS, REASONS FOR CAUTION

Despite the long half-lives of PBDEs and OH-BDEs, exposure misclassification is possible for women who underwent multiple treatment cycles over several months or years. It is also possible another medium, such as follicular fluid would be optimal to characterize exposure. We also tested associations for multiple congeners and metabolites with multiple outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Detections of serum concentrations of PBDEs and OH-BDEs were highest in the early years of the study and suggests that the phase-out of these compounds has contributed to a decrease in exposure. The negative associations found for PBDEs and IVF outcomes among other race women suggests the potential for racial disparity. Potential racial disparities in PBDE exposure and exploration of alternative flame retardants with reproductive health outcomes should be the focus of future investigations.

STUDY FUNDING/COMPETING INTEREST(S)

Funding for this research was supported by the National Institutes of Environmental Health Sciences (NIEHS) [R01 ES009718, ES022955, ES000002 and 009718T32ES007069]. The authors have no conflicts of interest.

Dietary Arthrospira platensis improves systemic antioxidant potential and changes plasma lipids without affecting related hepatic metabolic pathways in post-weaned piglets

BACKGROUND

The ability of a high level of dietary Arthrospira platensis, individually or in combination with two exogenous carbohydrate-degrading enzymes (lysozyme and Rovabio®), to improve systemic antioxidant potential and hepatic lipid metabolism was tested in piglets. Forty male post-weaned piglets, sons of Large White × Landrace sows crossed with Pietrain boars, were allocated into 4 groups (n = 10) and fed during 28 days one of the following diets: 1) a control basal diet (cereal and soybean meal); 2) a basal diet with 10% of A. platensis (AP); 3) the AP diet supplemented with 0.005% of Rovabio® (AP + R); 4) the AP diet supplemented with 0.01% of lysozyme (AP + L).

RESULTS

Arthrospira platensis decreased BW gain of piglets, regardless the addition of feed enzymes. The majority of plasma metabolites were affected by diets. A. platensis increased total lipids, total cholesterol and LDL-cholesterol, without changing hepatic fatty acid content or modulating, in an expressive manner, the transcriptional profile of lipid sensitive mediators. The antioxidant potential in general, and total carotenoids in particular, were improved by the microalga, regardless lysozyme or Rovabio®.

CONCLUSIONS

Summing up, A. platensis, individually and combined with feed enzymes, impacts negatively on piglets' growth but improves the systemic antioxidant potential and changes plasma lipids with a minor modulation on related hepatic metabolic pathways.

Neurobehavioural and cognitive effects of prenatal exposure to organochlorine compounds in three year old children

Background

We report data of a Belgian observational prospective cohort study regarding cognitive and behavioural development until the age of 36 months in relation to internal exposure to organochlorine pollutants [sum of polychlorinated biphenyls (sum PCB), dioxin-like activity, PCB118, PCB170, hexachlorobenzene (HCB) and p,p’-dichlorodiphenyldichloroethylene (DDE)] measured in cord blood.

Methods

Participants were recruited as part of an Flemish Environmental Health Survey (2002–2006). Two hundred and six mother-child pairs were recruited. Hundred twenty five toddlers [Reynell Taal Ontwikkelings Schalen (language development, RTOS), Snijders-Oomen Niet-verbale intelligentietest (non-verbal intelligence, SON), Bayley Scales, milestones, Infant Behaviour Questionnaire (IBQ), gender specific play behaviour, Neurobehavioral Evaluation System (NES)-attentional task] and their mothers [Home Observation Measurement of the Environment (HOME), Wechsler Abbreviated Scale of Intelligence (WASI), State-Trait Anxiety Inventory (STAI), general questionnaires] were tested. Statistical analysis was performed with the SPSS program. Much attention was paid to confounding factors.

Results

In the first years of development, higher organochlorine pollutants were associated with less active children (delayed crawling: sum PCB*HCB (p < 0.05), sumPCB*DDE (p < 0.1); delayed first steps alone: sum PCB (p < 0.5), PCB118 (p < 0.01), PCB170 (p < 0.01), HCB (p < 0.01); less switching between toys: sum PCB (p < 0.01); less switching between toys in boys: PCB118 (p < 0.01), sum PCB(p < 0.01)). At 12 months children with higher dioxin-like activity tended to show less fear responses(p < 0.1) (IBQ 12 months). At 36 months, a slower development of language comprehension (RTOS) was related to all organochlorine exposure parameters(p < 0.1 or p < 0.05) except DDE. Lower nonverbal IQ scores (SON) were related to PCB118 in boys only(p < 0.05 or p < 0.01). Less masculine and more non-gender specific play behaviour was associated with sum PCB in boys and girls at 36 months(p < 0.1). Moreover, PCB118 (p < 0.05), PCB170 (p < 0.1), HCB(p < 0.05) and DDE(p < 0.05) were associated with diminished masculine play behaviour in boys.

Conclusion

Our data confirm the observations that neurobehavioral development of young children is adversely influenced by environmental concentrations of PCBs, especially in boys. In this context, observation of play behaviour seems to be a reliable, easy to perform and sensitive test to detect neurotoxic effects of chemicals like PCB’s and dioxin-like compounds in very young children. On the basis of our results, we hypothesize that an underarrousal pattern may play a role in the spectrum of effects measured in toddlers prenatally exposed to PCBs and dioxin-like compounds.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02533-2.

Polybrominated diphenyl ethers in serum from residents living in a brominated flame retardant production area: Occurrence, influencing factors, and relationships with thyroid and liver function

Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants (FRs) in China for decades, even after they were identified as persistent organic pollutants. In this study, serum samples were collected from 172 adults without occupational exposure who were residents of a well-known FR production region (Laizhou Bay, north China), and PBDE congeners were measured to assess their occurrence, congener profile and influencing factors in serum. Moreover, the relationships between serum concentrations of PBDEs and thyroid/liver function indicators were analyzed to evaluate whether human exposure to PBDEs would lead to thyroid/liver injury. All 8 PBDE congeners were detected at higher frequencies and serum concentrations than those found in general populations. The median levels of ∑PBDEs, BDE-209 and ∑_3-7PBDEs (sum of tri-to hepta-BDEs) were 64.5, 56.9 and 7.2 ng/g lw (lipid weight), respectively, which indicated that deca-BDE was the primarily produced PBDE in Laizhou Bay and that the lower brominated BDEs were still ubiquitous in the environment. Gender was a primary influencing factor for some BDE congeners in serum; their levels in female serum samples were significantly lower than those in male serum samples. Serum PBDE levels showed a downward trend with increased body mass index (BMI), which might reflect the increasing serum lipid contents. Serum levels of some BDE congeners were significantly positively correlated with certain thyroid hormones and antibodies, including free triiodothyronine (fT3), total triiodothyronine (tT3), total thyroxine (tT4) and thyroid peroxidase antibody (TPO-Ab). Levels of some congeners were significantly negatively correlated with some types of serum lipid, including cholesterol (CHOL), low density lipoprotein (LDL) and total triglyceride (TG). Other than serum lipids, only two liver function indicators, total protein (TP) and direct bilirubin (DBIL), were significantly correlated with certain BDE congeners (BDE-100 and BDE-154). Our results provide new evidence on the thyroid-disrupting and hepatotoxic effects of PBDEs.

Soares B, Pimpão C, M. A. Pinto R, Costa T, Freire JPB, Corrent E, Chalvon-Demersay T, Prates JAM, Lopes PA, Soveral G. Glutamine and cystine-enriched diets modulate aquaporins gene expression in the small intestine of piglets

The regulation of glycerol permeability in the gastrointestinal tract is crucial to control fat deposition, lipolysis and gluconeogenesis. Knowing that the amino acid glutamine is a physiological regulator of gluconeogenesis, whereas cystine promotes adiposity, herein we investigated the effects of dietary supplementation with glutamine and cystine on the serum biochemical parameters of piglets fed on amino acid-enriched diets, as well as on the transcriptional profile of membrane water and glycerol channels aquaporins (AQPs) in the ileum portion of the small intestine and its impact on intestinal permeability. Twenty male piglets with an initial body weight of 8.8 ± 0.89 kg were allocated to four dietary treatments (n = 5) and received, during a four week-period, a basal diet without supplementation (control) or supplemented with 8 kg/ton of glutamine (Gln), cystine (Cys) or the combination of the two amino acids in equal proportions (Gln + Cys). Most biochemical parameters were found improved in piglets fed Gln and Cys diet. mRNA levels of AQP3 were found predominant over the others. Both amino acids, individually or combined, were responsible for a consistent downregulation of AQP1, AQP7 and AQP10, without impacting on water permeability. Conversely, Cys enriched diet upregulated AQP3 enhancing basolateral membranes glycerol permeability and downregulating glycerol kinase (GK) of intestinal cells. Altogether, our data reveal that amino acids dietary supplementation can modulate intestinal AQPs expression and unveil AQP3 as a promising target for adipogenesis regulation.

Serum levels of novel brominated flame retardants (NBFRs) in residents of a major BFR-producing region: Occurrence, impact factors and the relationship to thyroid and liver function

Five currently used novel brominated flame retardants (NBFRs) were determined in 172 serum samples collected from nonoccupational residents of a major BFR-producing region. All the 5 NBFRs presented high detection frequencies (DFs, >90%), and decabromodiphenyl ethane (DBDPE), a substitute of decabrominated diphenyl ethers (deca-BDE), was the most abundant NBFR. The levels of DBDPE were from <LOD to 1590 ng/g lw, with a median level of 32.5 ng/g lw. The median levels of other NBFRs were from 0.134 to 2.87 ng/g lw, which were at least 10 times lower than that of DBDPE. Moreover, a comparison to other studies showed that our results were significantly higher than studies conducted in background population. The levels of some NBFRs adjusted by serum lipid showed negative and significant correlation with BMI, whereas the difference disappeared when NBFRs levels were calculated based on serum volume. Certain NBFRs in female showed significantly higher concentrations than those in male. No significant effect of age, smoking habit, education level and children birth (in female) on serum NBFR levels was observed. The relationship between the serum levels of NBFRs and a series of thyroid/liver injury biomarkers was further analyzed to evaluate the health effects of these NBFRs to human being. Results showed that a 10-fold increment in the serum DBDPE level was associated with decreased total triiodothyronine (TT3) level (-0.037 nmol/L) [95% CI: -0.070, -0.003]， whereas serum pentabromoethylbenzene (PBEB) level was associated with increased total triiodothyronine (TT3) level (0.031 nmol/L) [95% CI: 0.001, 0.060]. For liver indicators, a 10-fold increment in the serum level of PBT was associated with decreased Ln aspartate aminotransferase/alanine aminotransferase (AST/ALT) level (-0.068) [95% CI: -0.129, -0.007]. A 10-fold increment in the serum level of BTBPE was associated with increased TBIL level (0.869 μmol/L) [95% CI: 0.175, 1.564], direct bilirubin (DBIL) level (0.231 μmol/L) [95% CI: 0.075, 0.388] and IDBIL level (0.638 μmol/L) [95% CI: 0.091, 1.185]. Our findings indicate that BFR production is posing heavy BFR contamination to surrounding environment and human being, and which might relate to thyroid disruption and liver injury.

Reproductive outcomes associated with flame retardants among couples seeking fertility treatment: A paternal perspective

BACKGROUND

Polybrominated diphenyl ethers (PBDEs) have been phased out of production for nearly a decade yet are still frequently detected in serum of U.S. adults. PBDE concentrations have been associated with adverse reproductive outcomes and laboratory studies suggest hydroxylated-BDEs (OH-BDEs) may act as endocrine disruptors. We set out to assess the joint effects of paternal and maternal serum PBDE concentrations on in vitro fertilization (IVF) outcomes and the association between paternal serum OH-BDE concentrations and IVF outcomes.

METHODS

This analysis included 189 couples (contributing 285 IVF cycles) recruited between 2006 and 2016 from a longitudinal cohort based at Massachusetts General Hospital Fertility Center who completed at least one IVF cycle and had an available blood sample at study entry. Congeners (47, 99, 100, 153, and 154) and OH-BDEs (3-OH-BDE47, 5-OH-BDE47, 6-OH-BDE47 and 4-OH-BDE49) were quantified in serum. Log-transformed PBDEs and OH-BDEs were modeled in quartiles for associations with IVF outcomes using multivariable generalized mixed models and cluster weighted generalized estimating equations.

RESULTS

Lipid-adjusted concentrations of PBDEs and OH-BDEs were higher in females than in male partners. There were no clear patterns of increases in risk of adverse IVF outcomes associated with PBDEs and OH-BDEs. However, some decreases in associations with IVF outcomes were observed in isolated quartiles.

CONCLUSIONS

Our assessment of couple level exposure is unique and highlights the importance of including male and female exposures in the assessment of the influence of environmental toxicants on pregnancy outcomes.

Impact of dietary incorporation of Spirulina (Arthrospira platensis) and exogenous enzymes on broiler performance, carcass traits, and meat quality

This study assessed the effect of Spirulina (Arthrospira platensis), individually and in combination with exogenous enzymes, on growth performance, carcass traits, and meat quality of broiler chickens. One hundred and twenty Ross 308 male chickens were allocated into 40 battery brooders, with 3 birds per cage, and fed ad libitum a corn-based diet during the first 21 D of the trial. The experimental period lasted from day 21 to 35, during which birds were fed 4 different diets: a corn-soybean basal diet, taken as the control group, a basal diet containing 15% Spirulina (MA), a basal diet containing 15% Spirulina plus 0.005% Rovabio Excel AP (MAR), and a basal diet containing 15% Spirulina plus 0.01% lysozyme (MAL). Body weight gain (P < 0.001) and feed conversion rate (P < 0.001) were improved in control chickens, when compared with those fed with Spirulina. In addition, Spirulina increased the length of duodenum plus jejunum in relation to the other treatment (P < 0.01). Chickens on the MAL diet showed a considerable increase in digesta viscosity (P < 0.05) compared with the control group. Breast and thigh meats from chickens fed with Spirulina, with or without the addition of exogenous enzymes, had higher values of yellowness (b*) (P < 0.001), total carotenoids (P < 0.001), and saturated fatty acids (P < 0.001), whereas n-3 polyunsaturated fatty acid (P < 0.01) and α-tocopherol (P < 0.001) decreased, when compared with the control. In conclusion, the incorporation of 15% Spirulina in broiler diets, individually or combined with exogenous enzymes, reduced birds' performance through a higher digesta viscosity, which is likely associated with the gelation of microalga indigestible proteins. In addition, cell wall of Spirulina was successfully broken by the addition of lysozyme, but not by Rovabio Excel AP. Therefore, we anticipate that the combination of lysozyme with an exogenous specific peptidase could improve the digestibility of proteins from this microalga and avoid their detrimental gelation.

Exposure to polycyclic aromatic hydrocarbons and risk for premature ovarian failure and reproductive hormones imbalance

Polycyclic aromatic hydrocarbons (PAHs) are a typical class of persistent organic pollutants that is ubiquitous worldwide. Previous animal studies suggested that PAHs had adverse effects on female reproduction. However, the human data regarding relationship of PAHs exposure with women reproductive health, such as ovarian dysfunction, are scarce. In this case-control study, the associations of serum levels of PAHs with the risk of premature ovarian failure (POF) and reproductive hormones in Chinese women were investigated, with recruiting 157 POF patients and 217 healthy women. The serum levels of 12 types of PAHs, as well as reproductive hormones, including follicle-stimulating hormone, luteinizing hormone and anti-mullerian hormone, were determined. In the logistic regression models, most individual PAH congeners showed significantly positive correlations with the risk of POF (p < 0.05), except for fluorine and pyrene. Benzo(a)pyrene (BaP), as the most carcinogenic PAH congener, was observed to be significantly positively associated with the risk of POF. After adjustment for age, body mass index, educational levels and household income, per one-unit increase in the log-transformed BaP concentration was significantly correlated with 2.191-fold increased risk of POF (OR = 2.191, 95%CI: 1.634-2.938, p < 0.05). To the best of our knowledge, this is the first study to report an association between internal exposure levels of PAHs and the increased risk of POF in women.

The challenging use and interpretation of blood biomarkers of exposure related to lipophilic endocrine disrupting chemicals in environmental health studies

The use of exposure biomarkers has been growing during the last decades, being considered the 'gold-standard' approach for individual exposure assessment to environmental chemicals. However, lipophilic endocrine disrupting chemicals (LEDC) have specific physicochemical and biological properties implying particular analytical challenges and interpretative caveats. The epidemiological literature is therefore afflicted by methodological inconsistencies and results divergences, in part due to recognised sources of exposure measurement error and misinterpretation of results. The aim of the present review is to identify external and endogenous sources of variability and uncertainty associated with the LEDC blood biomarkers in epidemiological studies. The dynamic nature of blood and an overview of the known mechanisms of transport, storage and partition of LEDCs in the organism are first described. The external sources of variability and uncertainty introduced at pre-analytical and analytical level are subsequently presented. Subsequently, we present some specific cases where the dynamics of lipids and LEDCs may be substantially modified and thus, the interpretation of biomarkers can be particularly challenging. The environmental obesogens as source of biomarkers variability is also discussed in the light of the most recent findings. Finally, different modelling approaches (statistical and pharmacokinetic models) proposed to improve the use and interpretation of biomarkers are appraised.

Thyroid function and decabromodiphenyl ethane (DBDPE) exposure in Chinese adults from a DBDPE manufacturing area

Polybrominated diphenyl ethers (PBDEs), which are persistent organic pollutants, affect thyroid function. Human exposure to decabromodiphenyl ethane (DBDPE), which has a similar structure to PBDEs, has recently increased, and the health effects of DBDPE have not been well studied. The objective of this study was to determine whether human exposure to DBDPE was associated with thyroid hormone levels in adults from a DBDPE manufacturing area. Three hundred-two blood samples were collected from two populations in the largest DBDPE manufacturing area located in North China: 133 DBDPE occupationally exposed workers from a DBDPE manufacturing plant and 169 non-DBDPE occupationally exposed residents from a nearby food processing plant. The levels of DBDPE, and thyroid function parameters [total thyroxine (TT4), free T4 (FT4), total triiodothyronine (TT3), free T3 (FT3), thyroid-stimulating-hormone (TSH), thyroglobulin antibody (TG-Ab), and thyroid peroxidase antibody (TPO-Ab)] were measured in serum samples. Serum concentrations of DBDPE ranged from 3.148 to 54,360 ng g^-1 lipid weight (lw), with a geometric mean of 332.6 ng g^-1 lw. A 10-fold increase in the DBDPE concentration was associated with increase of 4.73 nmol L^-1 [95% confidence interval (CI): 2.75, 6.71] TT4 and 0.046 nmol L^-1 TT3 [95% CI: 0.012, 0.081], corresponding to increases of approximately of 4.73% (95% CI: 2.75%-6.71%) and 2.38% (95% CI: 0.62%-4.20%), respectively. DBDPE in serum was also significantly and positively associated with the concentrations of TG-Ab and TPO-Ab. Our study found that exposure to DBDPE was associated with changes in thyroid activity in adults exposed to a high concentration of DBDPE, mainly increases of TT4, TT3, TPO-Ab, and TG-Ab. The association between DBDPE exposure and thyroid homeostasis requires further investigation because increasing DBDPE exposure has emerged in recent years.

Comparative Antidiabetic Activity of Aqueous, Ethanol, and Methanol Leaf Extracts of Persea americana and Their Effectiveness in Type 2 Diabetic Rats

Native to Mexico, Persea americana Mill. (avocado) is a fruit tree whose different parts (leaf, bark, roots, and stone) are used in traditional medicine especially against diabetes mellitus. The aim of this study was to investigate the beneficial effects of 28-day treatment with aqueous, ethanolic, and methanolic leaf extracts on glucose homeostasis in type 2 diabetic mellitus using Wistar rats. Type 2 diabetes was induced with nicotinamide (120 mg/kg, i.p.) and streptozotocin (65 mg/kg, i.p.). After 28 days of treatment, histopathological examination of the pancreas, kidneys, liver, and muscle (tibialis anterior) were realized. Biochemical markers were determined and an intestinal absorption test of D-glucose was performed. All extracts (100 mg/kg/day, p.o.) significantly (p < 0.001) reduced blood glucose level at the 28^th day of treatment with a more pronounced effect for methanolic extract. The treatments were well tolerated and induced a restoration of T-CHOL and HDL-C levels compared to the control group. Methanolic extract reduced the AIP (atherogenic index of plasma) by 45%. Histopathological analyzes of the pancreas showed regeneration of islets of Langerhans. Methanolic extract was the most effective in preventing intestinal glucose uptake up to 60.90% in relation to metformin. These results justify the use of this plant in traditional medicine against type 2 diabetes. However, other complementary studies should be done to identify the molecules responsible for this activity and their signaling voice.

Spatial and temporal distribution of p,p'-DDE (1‑dichloro‑2,2‑bis (p‑chlorophenyl) ethylene) blood levels across the globe. A systematic review and meta-analysis

BACKGROUND

Although p,p'‑DDT (1,1,1‑trichloro-2,2‑bis (p‑chlorophenyl)‑ethane) has been banned for decades in most countries, its major metabolite p,p'-DDE (1‑dichloro‑2,2‑bis (p‑chlorophenyl) ethylene) is still detected in the vast majority of human blood samples.

OBJECTIVES

The purpose of this study was to quantitatively estimate the geographical distribution of DDE blood levels and record time-trends for specific countries and continents, exploiting available data from the scientific literature.

METHODS

A literature search was performed in SCOPUS and PUBMED databases. Studies were screened at 2 levels applying different sets of inclusion/exclusion criteria. Blood levels of DDE along with other variables of interest were extracted, and a meta-analysis of random effects was conducted, by using the package metafor within the statistical programming language R. Results were expressed as pooled geometric means (GM [95% confidence intervals, CIs]).

RESULTS

A total of 418 papers were included in the quantitative synthesis that contained data for 854 population subgroups, and analyzed a total of 195,595 samples. Overall global DDE concentrations dropped from 5207 (95% CI: 3616-7499) ng/g lipids during 1951-1969 to 207 (95% CI: 159-269) ng/g lipids for studies reporting sampling after 2000. Analyses for studies published from 2001 and onward revealed geographical differences regarding DDE burden.

DISCUSSION

The significant decline in DDE blood levels after its restriction is demonstrated in our results. Differences in decrease trends were observed in different parts of the globe, which can be explained by deferred implementation of environmental policies. In some countries DDE concentrations remain high, and systematic biomonitoring is proposed.

Transplacental transfer of organochlorine pesticides: Concentration ratio and chiral properties

Currently, there is limited information about the mechanism of the human transplacental transfer for organochlorine pesticides (OCPs). This study aimed to evaluate the transplacental transfer of OCPs to better understand the influencing factors of exposure and transplacental efficiency. The study involved quantitative determination of OCPs and the enantiomer fraction (EF) of chiral OCPs in pregnant women from Wuhan, China. The results indicate that the exposure levels of OCPs varied in the order: maternal serum > cord serum > placenta. Chiral contaminants, such as α-HCH, o,p'-DDD and o,p'-DDT, were non-racemic in the three biological matrices, wherein EF_α-HCH < 0.5, EF_o,p'-DDD < 0.5, EF_o,p'-DDT > 0.5. For HCHs, the concentration ratio between cord serum and maternal serum (R_cm) <1, while for DDXs, the R_cm ≈ 1, indicating that the transport efficiency of different pollutants is related to the physicochemical properties. These results showed that placenta seems to be a more efficient barrier for β-HCH than for p,p'-DDE. The concentration ratios across placenta significantly lower than 1 and the enantiomeric selective transfer imply that some OCPs may have more complicated maternal-fetus transfer mechanisms, involving both simple diffusion and active transport. To the best of our knowledge, this is the first study to investigate the transfer of OCPs and their enantiomer fractions across placenta. These findings could expand the database of chemical exposure in biological matrices and improve the understanding of the mechanisms of transplacental transfer of OCPs.

Supporting dataset and methods for Transplacental Transfer of Organochlorine Pesticides: Concentration Ratio and Chiral Properties

The dataset and methods provided in this article supports "Transplacental Transfer of Organochlorine Pesticides: Concentration Ratio and Chiral Properties" [1]. The supplementary data were as follows: 1) the information on pretreatment and instrumental methods.2) the data for concentration in the maternal serum, cord serum and placenta samples and data interpretation. 3) the correlation between the influence factors and the log-transformed concentrations of the chemicals samples. 4) the dataset for transplacental transfer ratio of the OCPs and correlations with influencing factors.

Selected persistent organic pollutants associated with the risk of primary ovarian insufficiency in women

Although some persistent organic pollutants (POPs) may not be currently in production, many of these chemicals still exist ubiquitously in the environment and continue to represent significant environmental health concern. One of the important concerns of POPs exposure may lead to the adverse reproductive consequences including primary ovarian insufficiency (POI), but the limited evidence has been reported so far. Our case-control study was performed to explore the association between serum levels of selected POPs and risk for POI in a Chinese female population, including 157 cases and 217 healthy controls. Serum concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and serum levels of reproductive hormones [follicle-stimulating hormone (FSH), luteinizing hormone (LH), anti-Mullerian hormone (AMH) and estradiol] were measured. The medians of dioxin-like PCBs (DL-PCBs) and p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) were significantly higher in case sera than in controls. Higher concentrations of DL-PCBs and p,p'-DDT were significantly associated with elevated risk of POI. A dose-response relationship was observed between the sum of DL-PCBs (Σ₆ DL-PCBs) and the risk of POI (p for trend = 0.003), with odds ratios for the second and third tertiles, compared with the first, of 1.31- (95% CIs: 0.67-2.57) and 3.15-fold (95% CIs: 1.63-6.10), respectively. Similar results were observed for the sum of p,p'-DDT and its metabolites (Σ₂ p,p'-DDTs). In control women, FSH levels were negatively associated with PCBs exposure, while LH had a positive association with OCPs. In patients with POI, exposure to PCBs was correlated with higher levels of LH, whereas exposure to OCPs was associated with lower levels of AMH. To the best of our knowledge, this study for the first provided evidence that exposure to PCBs and DDT could be the potential risk factors for POI in women.

Polychlorinated Dibenzo-p-Dioxins, Polychlorinated Dibenzofurans, and Dioxin-Like Polychlorinated Biphenyls in Umbilical Cord Serum from Pregnant Women Living Near a Chemical Plant in Tianjin, China

Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and dioxin-like polychlorinated biphenyls (dl-PCBs) are bioaccumulative compounds that may affect fetal growth and infant development. The aim of this study was to determine whether the pregnant women living near a chemical plant in Tianjin had a risk of exposure to dioxins. Concentrations of PCDD/Fs and dl-PCBs in 24 umbilical cord serum samples collected from pregnant women were measured using a high-resolution gas chromatograph with a high-resolution mass spectrometer (HRGC-HRMS) and an isotopic dilution method. The levels of ∑(PCDD/Fs + dl-PCBs) were in the range 476-8307 pg·g^-1 lipid, with a mean of 3037 pg·g^-1. The mean World Health Organization toxicity equivalent (WHO-TEQ) for PCDD/Fs and dl-PCBs was 14.0 and 2.14 pg·g^-1 lipid, respectively. The PCDD/Fs and dl-PCBs contributed 86.7% and 13.3%, respectively, to the total TEQ. The octa-CDFs and penta-CBs were predominant for the PCDD/Fs and dl-PCBs, accounting for 57.6% and 74.3%, respectively. Several PCDD/F and dl-PCB congeners were highly correlated, such as PCB 105 and PCB 118 (r = 0.982, p < 0.001). Although the results hint at decreasing trends for PCDD/F and dl-PCBs by comparison with a similar study in Tianjin, a total TEQ of 41.7% of study participants had a body burden that exceeded the biomonitoring equivalents for dioxins. It was shown that pregnant women and infants had a health risk of exposure to dioxins.

Exposure to Environmental Pollutants and Their Association with Biomarkers of Aging: A Multipollutant Approach

Mitochondrial DNA (mtDNA) content and telomere length are putative aging biomarkers and are sensitive to environmental stressors, including pollutants. Our objective was to identify, from a set of environmental exposures, which exposure is associated with leukocyte mtDNA content and telomere length in adults. This study includes 175 adults from 50 to 65 years old from the cross-sectional Flemish Environment and Health study, of whom leukocyte telomere length and mtDNA content were determined using qPCR. The levels of exposure of seven metals, 11 organohalogens, and four perfluorinated compounds (PFHxS, PFNA, PFOA, PFOS) were measured. We performed sparse partial least-squares regression analyses followed by ordinary least-squares regression to assess the multipollutant associations. While accounting for possible confounders and coexposures, we identified that urinary cadmium (6.52%, 95% confidence interval, 1.06, 12.28), serum hexachlorobenzene (2.89%, 018, 5.68), and perfluorooctanesulfonic acid (11.38%, 5.97, 17.08) exposure were positively associated ( p < 0.05) with mtDNA content, while urinary copper (-9.88%, -14.82, -4.66) and serum perfluorohexanesulfonic acid (-4.75%, -8.79, -0.54) exposure were inversely associated with mtDNA content. Urinary antimony (2.69%, 0.45, 4.99) and mercury (1.91%, 0.42, 3.43) exposure were positively associated with leukocyte telomere length, while urinary copper (-3.52%, -6.60, -0.34) and serum perfluorooctanesulfonic acid (-3.64%, -6.60, -0.60) showed an inverse association. Our findings support the hypothesis that environmental pollutants interact with molecular hallmarks of aging.

Time trends of persistent organic pollutants in 30 year olds sampled in 1986, 1994, 2001 and 2007 in Northern Norway: Measurements, mechanistic modeling and a comparison of study designs

BACKGROUND

Human biomonitoring studies have demonstrated decreasing concentrations of many persistent organic pollutants (POPs) in years after emission peaks.

OBJECTIVES

To describe time trends of POPs in blood using four cross-sectional samples of 30 year olds from Tromsø, Norway across 1986-2007, and to compare the measured concentrations of polychlorinated biphenyl 153 (PCB-153) to model-estimated values. A second objective was to compare the repeated cross-sectional time trends with those observed in our previous longitudinal study using repeated individual measurements in older men from the same surveys.

METHODS

Serum from 45 persons aged 30 years in each of the following years: 1986, 1994, 2001, and 2007 was analyzed for 14 POPs. Further, predicted concentrations of PCB-153 in each sampling year were derived using the emission-based CoZMoMAN model.

RESULTS

The median decreases in summed serum POP concentrations (lipid-adjusted) in 1994, 2001, and 2007 relative to 1986 were - 71%, - 81%, and - 86% for women and - 65%, - 77%, and - 87% for men, respectively. The overall time trend in predicted PCB-153 concentrations demonstrated agreement with the observed trend although model predictions were higher than the measured concentrations at all time points. Compared to our previous longitudinal study of repeated individual measurements in older men, similar although more prominent declines were observed in the younger cross-sectional samples.

DISCUSSION

Observed declines in serum concentrations from 1986 to 2007 were substantial for legacy POPs in men and women at reproductive ages in Northern Norway and are generally consistent with previous longitudinal biomonitoring efforts in the study population. The measured concentrations and observed declines likely reflect a combination of recent and historic exposures. Small differences in time trends observed between the studies could be attributed to different study designs (i.e. the chosen age group or sex and cross-sectional versus repeated individual measurement sampling).

Disruption of thyroid hormone levels by decabrominated diphenyl ethers (BDE-209) in occupational workers from a deca-BDE manufacturing plant

While there is some evidence that exposure to decabrominated diphenyl ethers (BDE-209) affects thyroid function, the results obtained to date have been inconsistent. No studies have been performed on workers in deca-BDE manufacturing who had a high level of exposure to BDE-209 and relatively little exposure to other contaminants. In the present study, the relationship between BDE-209 exposure and thyroid hormone in occupational workers from a deca-BDE manufacturing plant was investigated. The serum and urine levels of polybrominated diphenyl ethers (PBDEs) and serum thyroid hormones were measured in 72 workers recruited from the deca-BDE manufacturing plant. The associations between their thyroid hormone levels and their exposure to BDE-209 were examined using multiple linear regression models. Serum concentrations of BDE-209 ranged from 67.4 to 109,000 ng/g lipid weight (lw), with a median of 3420 ng/g lw, contributing to 93.1% of the total PBDEs. The concentration of BDE-209 in urine was highly correlated with that in the serum (r² = 0.440, p < 0.001), indicating that urine may be a good non-invasive biomonitoring medium of BDE-209 body burden in occupational workers. BDE-209 in the serum was significantly and positively correlated with total thyroxine (tT4, r = 0.270, p = 0.029) and marginally and positively correlated with total triiodothyronine (tT3, r = 0.232, p = 0.061) in all occupational workers after adjusting for gender, age, BMI, and occupational exposure duration. A 10-fold increase in the serum BDE-209 concentration was associated with an increase in tT4 (8.63 nmol/L) [95% confidence interval (CI): 0.930-16.3] and tT3 (0.106 nmol/L) [95% confidence interval (CI): -0.005-0.219], corresponding to the increase of 7.8% in tT4 level and 5.4% in tT3 level. Associations between urine BDE-209 levels and thyroid hormones were similar to the results for the serum levels. These findings offer new evidence for proving the thyroid disrupting effects of BDE-209, impacting the direction of hyperthyroidism.