Dietary exposures to food contaminants across the United States

Protocol for pesticide residue monitoring and risk assessment on water, sediment, and fish: A case study of two selected reservoirs in Ghana

Background

Africa is experiencing a significant surge in the use of pesticides on farms. Though the use of pesticide products on farms is increasing rapidly, the ability to monitor and regulate the practice has not kept pace. Despite their potential significance, the health and environmental impacts of the growing pesticide usage in developing nations remain inadequately comprehended and recorded.

Objective

This paper presents a research protocol for a study that seeks to provide criteria for future monitoring of pesticide residues in aquatic environments and food sources. This study aims to evaluate pesticide utilisation methods and the potential hazards of pesticide residues in aquatic ecosystems. Additionally, the study seeks to assess the human health risks linked to pesticide applications.

Methods

This study will employ a quantitative approach and cross-sectional design. It will utilise a combination of survey and the collection of biological and environmental samples. Our methodology consists of four distinct steps. These outline the processes for studying pesticide residue in environmental and fish samples. Additionally, we plan to employ mathematical algorithms to evaluate the ecological and health risks associated with these pesticide residues.

Conclusion

This study is an effort to monitor and assess the hazards to the environment and human well-being associated with the increasing utilisation of pesticides. It also aims to gather relevant data on pesticide utilisation practices that contribute to the contamination of aquatic ecosystems. It will specifically focus on determining the concentration of pesticide residues in both biological and environmental samples. Additionally, the study will assess the ecological and health risks associated with these pesticide residues. This will enable the incorporation of organised research efforts and coordinated pesticide surveillance operations for toxicovigilance.

The Bioaccessibility and Bioavailability of Pentachlorophenol in Five Animal-Derived Foods Measured by Simulated Gastrointestinal Digestion

Pentachlorophenol (PCP) is a ubiquitous emerging persistent organic pollutant detected in the environment and foodstuffs. Despite the dietary intake of PCP being performed using surveillance data, the assessment does not consider the bioaccessibility and bioavailability of PCP. Pork, beef, pork liver, chicken and freshwater fish Ctenopharyngodon Idella-fortified by three levels of PCP were processed by RIVM and the Caco-2 cell model after steaming, boiling and pan-frying, and PCP in foods and digestive juices were detected using isotope dilution-UPLC-MS/MS. The culinary treatment and food matrix were significantly influenced (p < 0.05) in terms of the bioaccessibility and bioavailability of PCP. Pan-frying was a significant factor (p < 0.05) influencing the digestion and absorption of PCP in foods, with the following bioaccessibility: pork (81.37-90.36%), beef (72.09-83.63%), pork liver (69.11-78.07%), chicken (63.43-75.52%) and freshwater fish (60.27-72.14%). The bioavailability was as follows: pork (49.39-63.41%), beef (40.32-53.43%), pork liver (33.63-47.11%), chicken (30.63-40.83%) and freshwater fish (17.14-27.09%). Pork and beef with higher fat content were a key factor in facilitating the notable PCP bioaccessibility and bioavailability (p < 0.05). Further, the exposure of PCP to the population was significantly reduced by 42.70-98.46% after the consideration of bioaccessibility and bioavailability, with no potential health risk. It can improve the accuracy of risk assessment for PCP.

Enrichment, bioaccumulation and human health assessment of organochlorine pesticides in sediments and edible fish of a plateau lake

The organochlorine pesticides (OCPs) are with features of persistence, high toxicity, bioaccumulation and adverse impact on ecosystems and human beings. Although OCPs pollutions have been observed in the plateau lakes, comprehensive understandings in the distribution characteristics and human health risks of OCPs in these valuable but fragile ecosystems are limited. We here investigated the distribution, bioaccumulation process and health risks of OCPs in the Jianhu lake, a representative plateau lake in China. The endrin ketone, endrin aldehyde and heptachlor were the most dominant species in surface and columnar sediments. Their total contents ranged between 0 ~ 1.92 × 103 ng·g-1. The distribution of OCPs in sediment cores combined with chronology information indicated that the fast accumulation of OCPs happened during the last decades. Combining the distribution features of OCPs in different sources with mixing model results of carbon isotope (δ13C), farming area was identified as the main source (46%), and the OCPs were transported to lake by inflow-rivers (37%). The enrichment of OCPs in sediments caused considerable bioaccumulation of OCPs in local fish (∑OCPs 0-3199.93 ng·g-1, dw) with the bio-sediment accumulation factor (BSAF) ranging from ND to 9.41. Moreover, growing time was another key factor governing the accumulation in specific species (Carassius auratus and Cyprinus carpio). Eventually, the carcinogenic risk index (CRI) and exposure risk index (ERI) of the endrin category and aldrin exceeded the reference value, indicating relatively high health risks through consumption of fish. Overall, this study systematically illustrated the bioaccumulation process and health risks of OCPs in the typical plateau lake, providing theoretical support for the better protection of this kind of lakes.

The burden of chronic kidney disease associated with dietary exposure to cadmium in China, 2020

Cadmium (Cd) exposure increases the risk of chronic kidney disease (CKD). But the contribution of dietary Cd intake, the primary exposure route of Cd in humans, to the CKD burden remains to be evaluated in China. Concentrations of Cd in foods and population glomerular filtration rate (GFR) were retrieved from studies published between January 2000 and February 2023 in China. Daily food consumption in adults aged ≥35 years old was obtained from two nationwide Chinese surveys. Dietary Cd intake and its contribution rate among total Cd exposure from diet, inhalation, smoking and water were evaluated. Urinary Cd (UCd) was estimated using the toxicokinetic (TK) model based on dietary Cd intake. The effect of Cd on kidney function has been quantified with the previously published dose-response relationship between UCd and GFR. The incidence and disability-adjusted life years (DALYs) of CKD attributable to dietary Cd intake were derived considering the contribution rate of dietary Cd intake at the national and provincial levels. The national average dietary Cd intake was 0.6891 μg/kg bw/day, contributing 63.69% of total Cd exposure. The Cd exposure through foods resulted in 2.34 (95% uncertainty interval, UI: 1.54-3.40) stage 4 CKD and 0.37 (95% UI: 0.20-0.59) stage 5 CKD cases per 100,000 persons/year in mainland China, 2020. The corresponding DALYs loss associated with stage 4 and stage 5 CKD due to dietary Cd intake were 5.14 (95% UI: 3.24-7.67) and 4.78 (95% UI: 2.32-8.30) per 100,000 persons/year, together accounting for 2% of total DALYs of CKD. Greater dietary Cd intake and corresponding burden of late-stage CKD were observed in Southern areas than in Northern areas. Diet remains the primary exposure to Cd in Chinese adults. Efforts to reduce dietary Cd exposure would positively impact public health, especially in Southern provinces with high Cd exposure.

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in adipose tissue of women from Grand Tunis and their association with demographic factors and dietary habits

Dichlorodiphenyl trichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB) and polychloronated biphenyls (PCBs) were measured in 25 woman adipose tissues collected in 2016 from Grand Tunis, Tunisia. p,p'-DDE, p,p'-DDT, HCB and β-HCH were the dominant organochlorine pesticides (OCPs) in decreasing order in all samples. The total OCP levels varied from 79 to 343 ng g-1 lipid with a median value of 189 ng g-1 lipid and DDTs contributed approximately 88% to sum OCP. The ratio of p,p'-DDT/p,p'-DDE across all samples is below one, which suggests mainly historic exposure but may indicate some recent exposure to the banned pesticide. The median concentration of PCBs was 109 ng g-1 lipid and ranged between 27 and 204 ng g-1 lipid. PCB-153, PCB-180, PCB-138 and PCB-170 were the most abundant congeners, which contributed about 78% of the total PCBs. Spearman analysis showed that dominant organochlorine compounds (OCs) are highly positive correlated except for PCB-28/31, indicating that women from Tunis are exposed via similar routes. Inhalation exposure could be a possible pathway for the uptake of the less chlorinated congeners. We found positive and statistically significant association with subjects age for HCB (r = 0.517; p = 0.009) and PCBs (r = 0.65; p = 0.001) levels and a weak age-dependent accumulation was found for HCHs (r = 0.375; p = 0.065) and DDTs (r = 0.388; p = 0.056). The concentrations of OC subgroups were not associated with BMI, parity and residence. No association was observed between fish, red/white meat, milk and dairy products consumption and levels of HCB, HCHs and PCBs. DDTs levels were significantly correlated only with milk (p = 0.048) and milk products (p = 0.047) intake.

Contaminant containment for sustainable remediation of persistent contaminants in soil and groundwater

Contaminant containment measures are often necessary to prevent or minimize offsite movement of contaminated materials for disposal or other purposes when they can be buried or left in place due to extensive subsurface contamination. These measures can include physical, chemical, and biological technologies such as impermeable and permeable barriers, stabilization and solidification, and phytostabilization. Contaminant containment is advantageous because it can stop contaminant plumes from migrating further and allow for pollutant reduction at sites where the source is inaccessible or cannot be removed. Moreover, unlike other options, contaminant containment measures do not require the excavation of contaminated substrates. However, contaminant containment measures require regular inspections to monitor for contaminant mobilization and migration. This review critically evaluates the sources of persistent contaminants, the different approaches to contaminant remediation, and the various physical-chemical-biological processes of contaminant containment. Additionally, the review provides case studies of contaminant containment operations under real or simulated field conditions. In summary, contaminant containment measures are essential for preventing further contamination and reducing risks to public health and the environment. While periodic monitoring is necessary, the benefits of contaminant containment make it a valuable remediation option when other methods are not feasible.

Evaluating non-targeted analysis methods for chemical characterization of organic contaminants in different matrices to estimate children's exposure

BACKGROUND

Children are vulnerable to environmental exposure of contaminants due to their small size, lack of judgement skills, as well as their proximity to dust, soil, and other environmental sources. A better understanding about the types of contaminants that children are exposed to or how their bodies retain or process these compounds is needed.

OBJECTIVE

In this study, we have implemented and optimized a methodology based on non-targeted analysis (NTA) to characterize chemicals in dust, soil, urine, and in the diet (food and drinking water) of infant populations.

METHODS

To evaluate potential toxicological concerns associated with chemical exposure, families with children between 6 months and 6 years of age from underrepresented groups were recruited in the greater Miami area. Samples of soil, indoor dust, food, water, and urine were provided by the caregivers, prepared by different techniques (involving online SPE, ASE, USE, QuEChERs), and analyzed by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Data post-processing was performed using the small molecule structure identification software, Compound Discoverer (CD) 3.3, and identified features were plotted using Kendrick mass defect plot and Van Krevelen diagrams to show unique patterns in different samples and regions of anthropogenic compound classifications.

RESULTS

The performance of the NTA workflow was evaluated using quality control standards in terms of accuracy, precision, selectivity, and sensitivity, with an average of 98.2%, 20.3%, 98.4% and 71.1%, respectively. Sample preparation was successfully optimized for soil, dust, water, food, and urine. A total of 30, 78, 103, 20 and 265 annotated features were frequently identified (detection frequency >80%) in the food, dust, soil, water, and urine samples, respectively. Common features detected in each matrix were prioritized and classified, providing insight on children's exposure to organic contaminants of concern and their potential toxicities.

IMPACT STATEMENT

Current methods to assess the ingestion of chemicals by children have limitations and are generally restricted by specific classes of targeted organic contaminants of interest. This study offers an innovative approach using non-targeted analysis for the comprehensive screening of organic contaminants that children are exposed to through dust, soil, and diet (drinking water and food).

Exposure assessment of aflatoxins and zearalenone in edible vegetable oils in Shandong, China: health risks posed by mycotoxin immunotoxicity and reproductive toxicity in children

Human exposure to aflatoxins (AFs) and zearalenone (ZEA) has not been sufficiently investigated. Here, we analyzed the exposure level and health risks posed by AFs (B1, B2, G1, G2) and ZEA through cooking oil consumption in Shandong, China. The individual daily consumption of cooking oil was calculated through 2745 questionnaires during 2017-2019. The average contamination levels of mycotoxins were estimated by examining 60 cooking oil samples. For the peanut oil, AFs ranged from <0.2 to 274 μg/kg, with a positive rate of 66.6% (20/30). Average levels of 36.62 μg/kg AFB₁ and 44.43 μg/kg total AFs were found. Over-the-limit level (20 μg/kg) of AFB₁ was detected in 8/30 samples. Estimated daily intake (EDI) and margin of exposure (MOE) for age-stratified population groups showed that children are facing highest adverse health risk with AFB₁ (MOE 5.88-6.39). The liver cancer incidences attributable to AFB₁ exposure are non-negligible as 0.896, 0.825, and 0.767 cases per 100,000 for 6-14 age group, 15-17 age group, and adult labor-intensive workers. Over-the-limit level (60 μg/kg) ZEA contamination was detected in 25/30 corn oil samples with a 50th percentile value of 97.95 μg/kg. Our health risk assessment suggested significant health risks of enterohepatic (inflammation and cancer), reproductive, and endocrine systems posed by AFs and ZEA. However, the health risk of immunotoxicity is unclear because currently animal study data are not available for the immunotoxicity induced after long-term exposure. In general, the health risks posed by mycotoxins are non-negligible and long-term mycotoxin surveillance is necessary.

Human health risk surveillance of polychlorinated biphenyls in bovine milk from alluvial plain of Punjab, Pakistan

Punjab is the leading province of Pakistan in the production of bovine milk and its consumption. Rapid industrialization, high energy demand, and the production of waste have increased the risk of polychlorinated biphenyls (PCBs) toxicity in the environment. This research work was designed to assess human dietary exposure of ∑PCBs17 congeners through ingestion of buffalo and cow's milk from eight main districts of Punjab, Pakistan. The average concentrations of ∑DL-PCBs (8.74 ng g^-1 and 14.60 ng g^-1) and ∑I-PCBs (11.54 ng g^-1 and 18.68 ng g^-1) in buffalo and cow milk samples were analyzed, respectively. The PCB-156 was predominantly high congener found in both buffalo (2.84 ng g^-1) and cow milk (2.86 ng g^-1). It was found that the highest PCBs in bovine milk samples were observed in close vicinities of urban and industrial areas. The estimated daily consumptions of DL-PCBs and I-PCBs, from buffalo and cow milk, were below the acceptable daily intake for both adults and children. Moreover, hazard quotients (HQ) of the ∑PCBs17 congener value were less than 1.0 in adults and greater in the case of children reflecting the high chances of cancer. Furthermore, comprehensive monitoring for childhood cancer is recommended to establish the relationship in future studies.

Amyotrophic Lateral Sclerosis-Associated Persistent Organic Pollutant cis-Chlordane Causes GABAA-Independent Toxicity to Motor Neurons, Providing Evidence toward an Environmental Component of Sporadic Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease characterized by the death of upper and lower motor neurons. While causative genes have been identified, 90% of ALS cases are not inherited and are hypothesized to result from the accumulation of genetic and environmental risk factors. While no specific causative environmental toxin has been identified, previous work has indicated that the presence of the organochlorine pesticide cis-chlordane in the blood is highly correlated with ALS incidence. Never before tested on the motor system, here, we show that cis-chlordane is especially toxic to motor neurons in vitro- and in vivo-independent of its known antagonism of the GABA_A receptor. We find that human stem-cell-derived motor neurons are more sensitive to cis-chlordane than other cell types and their action potential dynamics are altered. Utilizing zebrafish larvae, we show that cis-chlordane induces motor neuron and neuromuscular junction degeneration and subsequent motor deficits in a touch-evoked escape response. Together, our work points to cis-chlordane as a potential sporadic ALS exacerbating environmental pollutant.

Organochlorine pesticides residue affinity in fish muscle and their public health risks in North West Ethiopia

Pesticides are the parent compounds, their metabolites, and associated impurities of agricultural and health chemical inputs. If they are found at concentration levels higher than the standard limits, they have potential negative impacts on the ecosystem in general and on fish and humans in particular. This study investigates organochlorine pesticides (OCPs) residue occurrences in fish muscle and assesses their public health potential risks, in North West Ethiopia. The concentration of OCPs residue under gas chromatography with electron capture detector (GC-ECD) was detected in 37.84% of fish muscle samples. The mean amounts detected were Endosalfan I, 341.50 ± 32.19 μg/kg; Endosalfan II, 36.01 ± 2.3 μg/kg; Endosalfan sulfate, 5.43 ± 4.06 μg/kg; 4, 4, DDE (4,4-dichlorodiphenyldichloroethylene), 64.01 ± 9.08 μg /kg; 4,4, DDD (4,4-dichlorodiphenyldichloroethane), 5.65 ± 3.12 μg/kg; and 4, 4, DDT (4,4-dichlorodiphenyltrichloroethane), 1.58 ± 0.30 μg/kg. The mean concentration of Endosalfan I tested in fish muscle samples was higher than that of the permissible limit of different international standards. However, due to the low per capita consumption rate of fish origin food in Ethiopia, the health risk index (HRI) ranges from 0.002 to 0.1275, which shows there is no public health risk. This study highlights the possibility of chemical residue occurrence in fish food products, and hence pesticide use regulations and monitoring concentration levels should be implemented regularly to avoid human and environmental health risks.

The occurrence and partition of total petroleum hydrocarbons in sediment, seawater, and biota of the eastern sea area of Shandong Peninsula, China

To investigate the occurrence and partition of total petroleum hydrocarbons (TPHs), sediment, seawater, and biota of the eastern sea area of Shandong Peninsula (China) were sampled in 2016. Due to shipping activities and discharge of industrial wastes, the TPH levels in the sediment decreased from the coastal areas to the offshore area. Waterborne TPH concentrations showed a decreasing order of autumn > summer > spring > winter, probably caused by low input of pollutants from the river into the ocean in dry seasons and frequent aquaculture operations in wet seasons. The distribution coefficient (logKd) between sediment and seawater ranged from 2.00 to 5.05, suggesting that TPHs are preferentially retained by the sediment. Significant positive correlations between logKd and total organic carbon (TOC), mud (fine particles), and temperature, as well as negative correlations between logKd and dissolved oxygen (DO), hydrogen ion concentration (pH), and oxidation-reduction potential (Eh), suggest interactions between environmental behaviors of TPHs and physicochemical factors. Mean bioaccumulation factors (BAFs) of TPHs in fish, shrimps, and mollusks were determined to be 240 ± 200, 900 ± 1800, and 2630 ± 1280, respectively, suggesting that considerable bioaccumulation occurs in shrimps when TPHs are transported from the seawater to the shrimps. A negative linear correlation between logTPHs and trophic level indicated biodilution of TPHs along the marine food web. This is the first study that has focused on the accumulation of TPHs in the entire sediment-seawater-biota system.

Agricultural pesticide residues in water from a karstic aquifer in Yucatan, Mexico, pose a risk to children's health

Yucatan is a region with a high impact of water contamination since it has a karst type soil favoring contaminants entry into the phreatic level, the only source of freshwater in the area. However, no studies report pesticides in water for human consumption or the risk it represents. The objective of this study was to detect and measure pesticide concentrations in domestic tap water to estimate the risk (carcinogenic and non-carcinogenic) to health. A non-probabilistic sampling was applied of 48 tap water sources, and then pesticide detection with solid-phase extraction gas chromatography coupled to the electron capture and flame photometric detectors allowed the estimation of risk through hazard ratios. The present results suggest that aldrin, heptachlor, and β-BHC residues in domestic tap water from Ticul, Yucatan, pose a risk to children's health, particularly for potential carcinogenic risks.

Freely dissolved organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) along the Indus River Pakistan: spatial pattern and risk assessment

Freely dissolved OCPs and PCBs were measured by using polyethylene passive samplers at 15 sites during 2014 throughout the stretch of the Indus River to investigate the spatial pattern and risk assess. Levels (pg/L) of dissolved ∑OCPs and ∑PCBs ranged from 34 to 1600 and from 3 to 230. Among the detected OCPs, dissolved DDTs (p,p'-DDE, followed by p,p'-DDT) predominated with levels of 0.48 to 220 pg/L. The order of occurrence for other studied OCPs was as follows: HCB, endosulfans, chlordanes, and HCHs. Spatially, dissolved (pg/L) ∑OCPs varied (p < 0.05) as the following: surface water of the alluvial riverine zone (ARZ) showed the highest levels (114) followed by the frozen mountain zone (FMZ) (52.9), low-lying zone (LLZ) (28.73), and wet mountain zone (WMZ) (14.43), respectively. However, our zone-wise PCB data did not exhibit significant differences (p > 0.05). Principal component analysis/multilinear regression results showed pesticide usage in the crop/orchard fields and health sector, electric and electronic materials, and widespread industrial activities as the main source of OCPs and PCBs along the Indus River. Our results showed that OCPs and PCBs contaminated water intake, playing an important role towards the considerable cancer/non-cancer risk (HI and CR values) along the Indus River Flood-Plain.

Effect of household culinary processes on organochlorine pesticide residues (OCPs) in the seafood (Penaeus vannamei) and its associated human health risk assessment: Our vision and future scope

Food safety is crucial in today's competitive trading market, as it directly affects human health and promotes seafood exports. The effects of thermal processing (boiling, frying, grilling, and microwave cooking) on pesticide residues (PR) in P. vannamei were assessed. The PR in raw and processed shrimp ranged from 0.007 to 0.703 μg/kg for uncooked/raw, not detected (ND) to 0.917 μg/kg for boiled, ND to 0.506 μg/kg for fried, ND to 0.573 μg/kg for grilled and ND to 0.514 μg/kg for microwave cooked shrimps. The Endrin, endosulfan sulfate, and heptachlor were predominant PR found in the raw and processed shrimp. The PR content in raw and cooked shrimps were below the maximum residue limits (MRL) set by the Codex Alimentarius Commission (2021) and the European Commission (86/363/1986 and 57/2007). The estimated daily intake (EDI) of PR from raw and processed shrimps were below the ADI prescribed by CAC. The hazard quotient (HQ) and hazard ratio (HR) values were <1, indicating no non-carcinogenic or carcinogenic health implications through shrimp consumption. The estimated maximum allowable shrimp consumption rate (CRlim) suggests an adult can eat >100 shrimp meals/month, which is over the USEPA's (2000)recommendation of >16 meals/month without health issues. The Effect of thermal processing was detected in the following order: boiling < grilling < frying < microwave cooking. The processing factor (PF < 0.7), paired t-test (t < 0.05), Tukey post hoc (p < 0.05) test, Bray-Curtis similarity index, and matrix plot exhibited that all the four thermal processing methods have a considerable impact on pesticides in the processed shrimps. But frying (59.4%) and microwave cooking (60.3%) reduced PR far beyond boiling (48.8%) and grilling (51.3%). Hence, we recommend frying and microwave processing are better methods for minimizing PR in seafood than boiling or grilling.

Bioaccumulation of current-use herbicides in fish from a global biodiversity hotspot: Lake St Lucia, South Africa

Agricultural pesticides threaten aquatic systems and biodiversity at a global scale, but limited information is available on the accumulation of current-use herbicides in tissues of aquatic organisms. Here, we examine the potential exposure and accumulation of currently used herbicides in two species of fish from Lake St Lucia, a global biodiversity hotspot located in South Africa. Muscle tissue samples were analysed for 11 widely used multi-residue and phenoxy-acid herbicides. Herbicide residues were detected in all samples analysed, with total concentrations ranging from 44.3 to 238 ng g^-1 (Clarias gariepinus) and 72.2-291 ng g^-1 dw (Oreochromis mossambicus). The most prominent herbicides detected included the two phenoxy-acid herbicides, MCPA (17.6 ± 12 ng g^-1) and 2,4-D (28.9 ± 16 ng g^-1), along with acetochlor (15.4 ± 5.8 ng g^-1), atrazine (12.7 ± 7.1 ng g^-1) and terbuthylazine (12.4 ± 12 ng g^-1). Results indicate that fish at Lake St Lucia accumulate a complex mixture of herbicides, some previously unreported in tissue, highlighting the potential threat that agricultural runoff may pose to conservation areas. However, assessing the impact of herbicide accumulation on wild fish populations is difficult at present and urgent toxicological data are needed to better understand chronic exposure effects on aquatic organisms. A preliminary human health risk assessment indicated minimal risk associated with the consumption of local fish, but potential additive and synergistic effects of contaminant mixtures remain unknown.

Spatial trends and human health risks of organochlorinated pesticides from bovine milk; a case study from a developing country, Pakistan

Bovine milk is a nutritious food commodity extensively produced and consumed in Punjab, Pakistan. This study assesses the concentration profile of organochlorine pesticides (OCP; 18 compounds) in buffaloes and cow's milk in eight major districts of Punjab, Pakistan and the potential impacts of such exposure. The total OCPs in buffaloes and cow's milk samples ranged from 3.93 to 27.63 ng mL^-1 and 14.64-77.93 ng mL^-1 respectively. The overall pattern of mean OCPs concentration in buffaloes and cows milk showed that Hexachlorocyclohexanes (HCHs) are predominant followed by Heptachlors and Dichlorodiphenyltrichloroethane (DDTs). So far, the concentration profile depicted that ∑HCHs, ∑DDTs and ∑Heptachlors did not exceed the maximum residual limits set for buffaloes and cow's milk. The spatial trends in terms of cluster analysis depicted significant variation (p > 0.05) among the districts in one cluster probably owing to local conditions. Furthermore, recently used DDTs were also identified at some of the selected districts. The risk assessment suggests that the estimated daily intake for each OCP was in accordance with the acceptable daily intake, thus single compound exposure does not pose a significant carcinogenic risk. However, the hazard ratios indicated that the values for ∑DDTs posed risk in adults consuming cow's milk whereas children may face carcinogenic risk on the consumption of both buffalo and cow's milk. The risk may be altered where mixture is considered, furthermore, regarding carcinogenic risks a continuous monitoring based ecological analysis is recommended in the future.

Organochlorine pesticide accumulation in fish and catchment sediments of Lake St Lucia: Risks for Africa's largest estuary

Although use of organochlorine pesticides (OCPs) has been banned or severely limited on a global basis, concerning concentrations continue to be reported in many tropical and subtropical regions of the world. These habitats often support high levels of unique biodiversity and vulnerable communities that depend on the environment for their survival. We investigated threats associated with OCP contamination at Lake St Lucia, a global hotspot for biodiversity and a UNESCO World Heritage Site in South Africa. Lake St Lucia is sustained largely by surface runoff from catchment areas where significant quantities of OCPs have historically been used in agriculture and where DDT continues to be used for disease control. Sediments (n = 40) collected from the two largest fluvial inputs to Lake St Lucia showed that these rivers represent important sources of contaminants, with ∑OCP concentrations ranging between 74 and 510 ng g^-1. Measured HCH, dieldrin, ∑DDT and ∑chlor concentrations exceeded NOAA sediment toxicity guidelines in the majority of samples analysed. Bioaccumulation was assessed by examining residue concentrations in muscle tissues from two abundant fish species from Lake St Lucia. OCPs were detected in all samples analysed, with total concentrations ranging 860-5000 ng g^-1 lw and 390-3200 ng g^-1 lw for Oreochromis mossambicus (n = 17) and Clarias gariepinus (n = 41), respectively. A health risk assessment indicated potential dietary risk associated with exposure to aldrin, dieldrin and heptachlor, although the cumulative effect of OCPs on human health, ecosystem biodiversity and long-term ecotourism sustainability remains unknown.

Contamination of Foods from Cameroon with Residues of 20 Halogenated Pesticides, and Health Risk of Adult Human Dietary Exposure

(1) Background: Halogenated pesticides are abundantly used in Cameroon, but there is no information on the health risk of consumers from exposure to their residues in foods. (2) Methods: Residues of 20 halogenated pesticides were determined in 11 agricultural products collected in the 3 largest cities of Cameroon using QuEChERS extraction and gas chromatography with electron capture detector (GC-ECD), and health risk from dietary exposure was assessed. (3) Results: Organochlorines pesticides aldrin, p,p'-dichlorodiphenyl-trichloroethane (DDT) and β-hexachlorocyclohexane (β-HCH) found in 85.0%, 81.9% and 72.5% of samples, respectively, were the most frequently detected. The highest average concentrations of residues were 1.12, 0.74 and 0.39 mg/kg for methoxychlor, alachlor and β-HCH, respectively, found in chilli pepper. Chili pepper (58.9%), cowpea (56.8%), black beans (56.5%) and kidney beans (54.0%) exhibited the highest residue occurrences. Levels above the European Union maximum residue limits (MRLs) were found for all the 20 pesticides, in 40.1% of the positive analyses, and the food samples contained 14 pesticides banned in Cameroon. Chronic, acute, cumulative and carcinogenic risk assessments revealed that lifetime consumption of maize, black beans, kidney beans, groundnuts and chili pepper contaminated with aldrin, dieldrin, endrin, HCB, heptachlor, o,p'-DDT, p,p'-DDD, p,p'-DDT, p,p'-DDE and β-HCH, could pose health risks. (4) Conclusion: These results show that there is an urgent need of pesticide usage regulation, effective application of pesticide bans and management of obsolete pesticide stocks in Cameroon.

Human health risk assessment of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) pesticide residues in fruits and vegetables in Nigeria

The residues of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) in forty-eight (48) composite fruit and vegetable samples (carrot, cucumber, tomato, and watermelon) were qualitatively and quantitatively determined using gas chromatography equipped with electron capture detector (GC-ECD). Safety indices such as the estimated average daily intake (EADI), cancer benchmark concentration (CBC), hazard quotient (HQ) and index (HI), and hazard ratio (HR) were also estimated. Results showed the predominance of HCH and its isomers in the fruits and vegetables as compared with the DDTs. The most predominant HCHs in all the fruits was α-HCH with mean concentrations of 2.704 ± 2.488 mg kg-1 (carrot), 1.536 ± 1.036 mg kg-1 (cucumber), 6.814 ± 2.967 mg kg-1 (tomato), and 9.241 ± 2.735 mg kg-1 (watermelon). The analysis showed that the levels of pesticide residues detected in 25 to 100% of the fruit and vegetable samples were above the UK/European Commission Maximum Residue Limits (MRLs). The non-carcinogenic health risk estimates showed that only α-HCH in tomatoes and watermelon had HQ > 1 which indicates the possibility of systemic health risk in children consumers. The carcinogenic health risk showed that only α-HCH and γ-HCH in children and α-HCH in adults had HR > 1 for tomato and watermelon which implies the possibility of carcinogenic health risk from its consumption. It is therefore paramount to institute a policy and regulatory framework for regular monitoring of pesticide residues in fruits and vegetables in Nigeria in order to ensure food safety for consumers and protect human health.

Occurrence and partition of organochlorine pesticides (OCPs) in water, sediment, and organisms from the eastern sea area of Shandong Peninsula, Yellow Sea, China

To evaluate the occurrence and partition of organochlorine pesticides (OCPs), hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs), water, sediment, and organisms were sampled from the eastern sea area of Shandong Peninsula (Yellow Sea, China) across all four seasons in 2016. There were three OCP hotspots in the sediment, mainly caused by the transportation of lindane and dicofol from adjacent Swan Lake and Guhe River. Waterborne OCP levels were highest in winter and lowest in spring, without vertical variability, suggesting that the Yellow Sea Cold Water Mass was governing the spatio-temporal distribution of OCPs in seawater. There was substantial accumulation of HCHs and DDTs in organisms via sediment, as indicated by the relatively low fraction of sedimental fugacity, high bio-sediment accumulation factor, and a positive linear correlation between logΣHCHs and trophic level. This is the first study that has focused on the accumulation of OCPs in entire sediment-seawater-organism system involving multi-phyla of species.

Levels and health risk assessment of organochlorine pesticide residues in vegetables from Yamaltu area in Gombe, Nigeria

The study determined the levels of organochlorine pesticides (OCPs) residues and assesses health risks linked with the consumption of vegetables cultivated in the Yamaltu area in Gombe, Nigeria. OCPs residues were solvent extracted and analyzed with a high performance liquid chromatography equipped with UV/VIS Detector. The mean concentrations of ten detected OCPs residues were almost all above the set limit of EU/WHOMRL. The estimated daily intake of OCPs from samples was below the acceptable daily intake, hazard index estimated were <1, indicated no probable non-carcinogenic health effect, while the carcinogenic health effect showed that children were more vulnerable for the consumption of the contaminated vegetables.

Nutrition and neurodevelopment: the search for candidate nutrients in the Seychelles Child Development Nutrition Study

This review examines the role of nutrients in child development and outlines the key nutrients identified as potentially important to neurodevelopment among high fish consumers in the Seychelles Child Development Nutrition Study (SCDNS). It describes the clinical assessment of these nutrients in the blood and breast milk samples collected from the cohort of 300 pregnant women who were recruited, at their first antenatal visit, on the SCDNS. These key nutrients include the long chain polyunsaturated fatty acids (LCPUFA), docosohexaenoic acid (DHA) and arachidonic acid (AA), both of which may affect neurodevelopment in the later stages of fetal growth. Only DHA, however, is strongly associated with fish consumption, the predominant source of the neurotoxicant methyl mercury (MeHg). Any benefits of increased selenium status on neurodevelopment are likely to accrue via detoxification of MeHg during fetal growth, while benefits of optimal iodine or thyroid status are likely to be directly related to neurodevelopment during late fetal growth. Unlike LCPUFA, Se, and I, the status of the B vitamins, folate, vitamin B12, vitamin B6, and riboflavin are unlikely to be closely related to fish consumption but the status of each of these B vitamins is likely to impinge on overall status of choline, which is expected to have direct effects on neurodevelopment both prenatally and postnatally and may also impact on MeHg toxicity. Choline status, together with the status of two other candidate nutrients, zinc and copper, which are also likely to have effects on neurodevelopment prenatally and postnatally, are expected to have some correlation with fish consumption.

New insights into the bioaccumulation of persistent organic pollutants in remote alpine lakes located in Himalayas, Pakistan

The current study assesses the persistent organic pollutants (POPs) in water and their bioaccumulation in Brown Trout (BT) and Rainbow Trout (RT) present in the remote alpine lakes (RALs) of Himalayas, Pakistan. Hence, these environments might receive POPs by long range atmospheric transport (LRAT) with little interferences from local anthropogenic activities. The potential transportation pathways for such accumulation can be atmospheric precipitation, melting ice and glacial runoff. The results indicated that the sum of mean concentrations of organochlorine pesticides (OCPs (DDTs + HCHs)) in water of Glacial-fed lakes, Ice melting-fed lake and Rain-fed lake ranged from 0.21 to 317, 0.14-293, 0.16-235 pg L-1, respectively, while those of polychlorinated biphenyls (PCBs) are 0.275-16.02, 0-15.88, 0.234-14.46 pg L-1, respectively. Similarly, the sum of mean concentrations of all investigated PCBs and OCPs in BT ranged from 0.008 to 0.715 ng g-1 and 0.003-3.835 ng g-1 based on wet weight (ww), while for RT these concentrations were 0.002-0.557 ng g-1 and 0.001-1.402 ng g-1 (ww), respectively in the selected RALs. The PCBs and OCPs levels in both water and fish tissues were observed in order of Glacial-fed lakes > Ice melting-fed lake > Rain-fed lake. The results proposed that melting of ice and glacial water are more significant sources of the contaminants (PCBs and OCPs) in the freshwaters of RALs of Himalayas as compared to rainfall water. The positive correlation between water contamination and the selected fish species confirmed that these can be used as a bio-indicator for future research studies. However, the impact of POPs as they cascade through downstream ecosystems remains largely unexplored. The additional study of contaminant dynamics should be extended to a wide range of mountain environments of Himalayas, where melt-water used for drinking and irrigation purposes by billions of people reside alone the waterways that originated from these remote areas.

Is dietary macronutrient intake associated with serum concentrations of organochlorine pesticides in humans?

In the general population, chronic exposure to low-dose persistent organic pollutants (POPs), particularly organochlorine pesticides (OCPs), has been recently linked to many chronic diseases. Widespread contamination of the food chain and human adipose tissue has made avoiding exposure to these chemicals impossible; thus, alternative strategies for decreasing the chemical burden must be investigated. Recently, macronutrient intake was found to significantly modify the toxicokinetics of POPs in animal experimental studies. Thus, we evaluated whether macronutrient intake was related to serum concentrations of OCPs in healthy adults without cardio-metabolic diseases. Subjects included 1,764 adults, aged 20 years or above, who participated in the National Health and Nutrition Examination Survey 1999-2004. Macronutrient intake was assessed based on a 24-h dietary recall interview. Six individual OCPs commonly detected among the general population were evaluated as markers of OCPs and other coexisting lipophilic chemicals stored in adipose tissue and released into circulation. High fat intake was associated with lower concentrations of OCPs, while high carbohydrate intake showed the opposite result. When three types of fats were individually evaluated, both saturated fatty acids and monounsaturated fatty acids, but not polyunsaturated fatty acids, were inversely associated with serum concentrations of OCPs. Adjustment for possible confounders did not change the results. When stratified by age, gender, body mass index, and physical activity, these associations were similar in most subgroups. Thus, similar to the findings observed in animal experimental studies, a moderate-fat diet with low carbohydrate intake was related to low serum concentrations of OCPs in humans. Although these findings need to be replicated, changing dietary macronutrient intake can be investigated as a practical strategy for dealing with unavoidable lipophilic chemical mixtures such as OCPs in modern society.

Regional characteristics of dietary lead intake in the Chinese population

Lead is known as a potent toxicant to human health and there is currently an issue with lead contamination of food in China. This study analysed the regional characteristics of dietary lead intake of the Chinese population and used this to assess the health risks for each region due to the presence of lead in different foods. Data of dietary lead intake was used from the 4th and 5th Chinese Total Diet Studies (CTDS) covering 12 to 20 provinces. Over 200 kinds of food samples were divided and analysed. Results showed that lead consumption varies from region to region, with some, such as Heibei, being at higher risk and consuming larger amounts, and others, such as Shanxi, being at lower risk. It was found that the spatial correlation between lead intake from meats and vegetables was 0.545. The strong association between meats and vegetables shows that lead contamination has a large effect on fresh foods. The food groups with the highest contribution to lead intake were cereals and vegetables, while the food categories with the lowest contribution were dairy products, sugar, and alcohol. The main food group contributing to lead intake in different regions was found to be cereals in Hebei, vegetables in Heilongjiang and Ningxia, and meats in Sichuan and Hunan. The food products contributing the most to lead intake were found to be kelp and nori in many provinces and other notable foods included processed and preserved soybean, meat, and fungus products. These results allow policy makers to better target their efforts when working on the issue of lead contamination, focusing on areas of high contamination, and to advise consumers to adjust their diets to avoid high risk foods as this issue is being resolved.

Occurrence and Human Health Risk of Dichlorodiphenyltrichloroethane (DDT) and Hexachlorocyclohexane (HCH) Pesticide Residues in Commonly Consumed Vegetables in Southwestern Nigeria

BACKGROUND

Fluted pumpkin (Telfairia occidentalis) and amaranth (Amaranthus spp.) are common leafy vegetables produced and consumed in southwestern Nigeria. These vegetables attract insect pests which are controlled by pesticides that may have adverse impacts on human health.

OBJECTIVES

To determine the levels of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) pesticide residues in the two vegetables and evaluate the potential health risks associated with their consumption.

METHODS

The pesticide residue levels were quantitatively and qualitatively determined using a gas chromatograph coupled with electron capture detector. Health risk assessment were performed using estimated average daily intake and hazard indices for two weight categories: children (16.7 kg) and adults (60 kg).

RESULTS

The results showed that delta-HCH, DDT and methoxychlor were predominantly detected in the two vegetables from both farms and markets. In amaranth, the mean concentration of methoxychlor, DDT and delta-HCH were 4.590 ± 2.774 mg/kg (dry weight (dw)), 0.757 ± 0.457 mg/kg (dw) and 0.577 ± 0.390 mg/kg (dw), respectively, while fluted pumpkin levels were 6.223 ± 2.489 mg/kg dw (methoxychlor), 0.504 ± 0.056 mg/kg dw (delta-HCH) and 0.486 ± 0.123 mg/kg dw (DDT). The levels of HCH and DDT residues were generally above the United Kingdom/European Commission maximum residue limit. The analysis of health risk estimates for non-carcinogenic risk revealed that for both vegetables, the hazard quotient for p, p' DDT and methoxychlor was >1 for both children and adults. The health risk estimates for carcinogenic risk revealed that hazard indices values were >1 for children for both vegetables and alpha-HCH had a hazard index >1 for adults for amaranth. This means the residue exceeds acceptable standard and present potential risk to consumers of these vegetables.

CONCLUSIONS

The results obtained from the present study indicate that consumption of amaranth contaminated with alpha-HCH could pose a carcinogenic risk for adult consumers. The consumption of the two vegetables could pose both non-carcinogenic and carcinogenic health risks to children and adults. Therefore, there is need for strict enforcement of regulations on pesticide usage to minimize human health risks.

COMPETING INTERESTS

The authors declare no competing financial interests.

Dietary exposure assessment of organochlorine pesticides in two commonly grown leafy vegetables in South-western Nigeria

Organochlorine pesticides (OCPs) are persistent pesticides whose usage have been banned or restricted worldwide and the presence of its residues in vegetables could affect its nutritional quality as well cause adverse health effects. This study quantified the OCP residue levels in commonly grown and consumed vegetables and assessed the carcinogenic and non-carcinogenic health risks from the consumption of the contaminated vegetables. The OCP residues levels in the extract from the vegetables were determined using a Gas Chromatograph coupled with Electron Capture Detector (GC-ECD). Health risk estimates were analysed using Estimated Average Daily Intake (EADI), Hazard Index (HI), and Hazard Ratio (HR) for children (16.7 kg) and adults (60 kg) weight categories. The residue analysis indicated that amaranths had the highest mean concentration of endrin aldehyde (2.987 ± 0.391 mg kg^-1) and endosulfan sulfate (0.661 ± 0.280 mg kg^-1), while in fluted pumpkin, the highest mean concentrations were endrin aldehyde (3.491 ± 0.376 mg kg^-1) and endosulfan sulfate (2.775 ± 0.644 mg kg^-1). The percentage of the detected OCP residues above Maximum Residue Limits (MRLs) ranged from 25% to 100% for both vegetables. Non-carcinogenic health risk estimates for the children weight category showed that aldrin, dieldrin, endrin, endrin aldehyde, and heptachlor detected in both vegetables had HI > 1. While for adults, only aldrin, dieldrin, endrin, and endrin aldehyde revealed non-carcinogenic effect in both vegetables. Human risk estimations for the carcinogenic health effect for the two vegetables showed that aldrin and dieldrin could pose carcinogenic health risks to adult, while aldrin, dieldrin, heptachlor and heptachlor epoxide could pose carcinogenic health risks to children. The results revealed both non-carcinogenic and carcinogenic health risks for the consumers of the contaminated vegetables from the selected locations in South-western Nigeria.

Trace elements and POPs in two commercial shark species from Djibouti: Implications for human exposure

Within Djibouti (Gulf of Aden), the scalloped hammerhead shark (Sphyrna lewini) and milk shark (Rhizoprionodon acutus) are important components of the artisanal fishery and they are caught to be exported or sold for local consumption. However, little scientific information exists on the contamination load of these species in this area of the world. With global populations of elasmobranchs in decline, understanding the extent of contaminant exposure is critical to future conservation as well as to assess the health risks for consumers of these species. The contaminants analyzed in this study comprised PCB, DDT and trace elements in livers, muscles and fins of both hammerhead sharks and milk sharks. The overall organochlorine compounds (OCs) and trace elements concentrations were similar among the two sharks' species and the pattern of PCB and DDT tissue distribution showed the highest burdens in livers compared with muscles and fins. However, the different accumulation profiles of OCs among shark species suggest species-specific accumulation of these contaminants. The p,p'DDE/∑DDT ratios were equal or slightly higher than the critic value of 0.6, suggesting possible recent inputs of technical DDT in the area. Concentration of trace elements from this study were generally comparable to those found in sharks from other areas of the world and, highlight the wide variation in metal concentrations between species, individuals and tissues. As far as Hg is concerned, scalloped hammerhead sharks showed higher accumulation in muscles compared with milk sharks. Both species showed elevated concentration of Se, which might be related to high Hg levels since Se inhibits Hg toxicity. The potential cancer risk for PCB, Cd, Ni, Cr and As fell within the range of 10^-6-10^-4, suggesting some concerns for the overall contamination levels in both species. Indeed, consuming of fish involves a mixture of all analyzed elements, and therefore, some potential risk might arise from regularly consuming these species.

Occurrence of perfluorinated compounds in agricultural environment, vegetables, and fruits in regions influenced by a fluorine-chemical industrial park in China

The occurrence of perfluorinated compounds (PFCs) in vegetables and fruits, as well as agricultural environment, was investigated in the downstream regions of Changshu fluorine-chemical industrial park (CFCIP) in China. Twenty-one PFCs were analyzed in irrigation water, agricultural soil, typical vegetables, and fruits, with the maximum total PFC concentrations of 369.9 ng/L, 64.7 ng/g dw, 11.5 ng/g ww, and 10.5 ng/g ww, respectively. Short-chained perfluoroalkyl carboxylic acids (PFCAs) such as perfluorooctanoic acid (PFOA), perfluorobutanoic acid (PFBA), and perfluorohexanoic acid were the dominant PFCs in terms of their concentrations and detection frequency. PFCs in irrigation water and agricultural soils showed a decreasing trend with increasing distance from CFCIP, while this pattern was not observed in agricultural products. The predominant compounds varied in different vegetables and fruits. Simultaneous bioaccumulation of PFBA and PFOA was found in melons and solanaceous species and pears. Leafy vegetables and grapes exhibited high bioaccumulation of PFOA and PFBA, respectively. Health risk assessment by calculating estimated daily intake showed that no direct risk was caused by the consumption of vegetables and fruits for the residents in the investigated regions. However, the tolerable weekly intake of PFOA exceeded the established thresholds for the adult residents. A comprehensive health assessment of the dietary exposure of PFCs, including all exposure pathways, in fluorine-chemical industrial park-impacted regions is needed.

Dietary exposure and risk assessment of organochlorine pesticide residues in rural communities living within catchment areas of iSimangaliso World Heritage Site, South Africa

Dietary intake of contaminated food is a major route of human exposure to organochlorine pesticides (OCPs). Despite the prevalence of OCP usage in southern Africa for several decades, their impact on socioeconomically vulnerable communities remains largely overlooked. We investigated the accumulation of OCPs in crops commonly cultivated by rural communities surrounding iSimangaliso Wetland Park, South Africa. All samples analysed were found to be contaminated, with total OCP concentrations ranging between 190 and 240 ng g^-1 ww. Elevated levels of OCP residues were detected in all products, with the majority of samples exceeding European Commission's maximum residue limits (MRLs). We combine these results with local OCP fish tissue estimates to assess potential dietary risks. Cumulative risk assessment indicated potential non-cancer risks associated with heptachlor epoxide, while a cancer risk as high as 1 in 10 was found to be associated with aldrin and dieldrin. This far exceeds USEPA guidelines and indicates that OCP residues in crops and fish from the study area pose a high risk to human health. The results of this study call for further attention to be given to the health implications of continued OCP use not only within the study area but also in Southern Africa in general.

Model-based exploration of the variability in lake trout (Salvelinus namaycush) bioaccumulation factors: The influence of physiology and trophic relationships

Because dietary consumption of fish is often a major vector of human exposure to persistent organic pollutants (POPs), much effort is directed toward a quantitative understanding of fish bioaccumulation using mechanistic models. However, many such models fail to explicitly consider how uptake and loss rate constants relate to fish physiology. We calculated the bioaccumulation factors (BAFs) of hypothetical POPs, with octanol-water partition coefficients ranging from 10^4.5 to 10^8.5 , in lake trout (Salvelinus namaycush) with a food-web bioaccumulation model that uses bioenergetics to ensure that physiological parameters applied to a species are internally consistent. We modeled fish in 6 Canadian lakes (Great Slave Lake, Lake Ontario, Source Lake, Happy Isle Lake, Lake Opeongo, and Lake Memphremagog) to identify the factors that cause the BAFs of differently sized lake trout to vary between and within lakes. When comparing differently sized lake trout within a lake, larger fish tend to have the highest BAF because they allocate less energy toward growth than smaller fish and have higher activity levels. When comparing fish from different lakes, the model finds that diet composition and prey energy density become important in determining the BAF, in addition to activity and the amount of total energy allocated to growth. Environ Toxicol Chem 2019;38:831-840. © 2019 SETAC.

Risk assessment of some organic contaminants: a case study based on food consumption in Tanta and Ismailia cities, Egypt

The impact of some organic pollutants on some residents of Tanta and Ismailia cities of Egypt through their consumption of vegetables, fruits and fish (Nile tilapia and catfish) was examined. Residues of organochlorine (OC_S) and organophosphorus (OP_S) as some polychlorinated biphenyls (PCB_S) were compared with pesticides as well maximum residue limits (MRL_S). Probable health risk to consumers was also assessed. P, P'-DDT, P, P'-DDE, P, P'-DDD, endrin, α-BHC, (lindane), and hexachlorbenzene (HCB) were the most detected organochlorine compounds, but did not exceed MRLs.However, OP_S residues were the most frequently detected contaminants. PCBs congeners 28, 70, 52, and 180 were detected in tilapia fish from Tanta, but congeners 28 and 180 were the only detected congeners in samples collected from Ismailia region. ∑PCB_S values in all matrices did not exceed MRL_S. Hazard index (HI) exhibited unity for all compounds at 50 the decreasing order: catfish > vegetables > fruits > Nile tilapia in Tanta, while in Ismailia the order was Nile tilapia > fruit > vegetables. Results also revealed that risk values for adults were greater than those of children categories.

Risk Of Human Dietary Exposure To Organochlorine Pesticide Residues In Fruits From Ghana

The objectives of this present study were to assess the level of organochlorine pesticide (OCP) residues in fruits and to determine the potential health risks associated with the exposure to these pesticides. A total of 120 fruits (watermelon, pineapple, and banana) were collected from five communities and a local market within the Mampong Municipality and analyzed for organochlorine pesticide residues. The results showed that the concentrations ranged from not detectable (ND)-48.22 ng/g for DDTs, ND-19.03 ng/g for HCHs, ND-4.10 ng/g for CHLs, ND-22.84 ng/g for Aldrin, and ND-11.53 ng/g for other OCPs. Levels of methoxychlor, Aldrin and gamma-hexachlorocyclohexane (HCH) exceeded the maximum residue limits in watermelon. Estimated health risk revealed that Aldrin in watermelon could pose potential toxicity to the consumer. Estimated average daily intake for Aldrin was above the acceptable average daily intake.

Fish consumption from urban impoundments: What are the health risks associated with DDTs and other organochlorine pesticides in fish to township residents of a major inland city

Organochlorine pesticides (OCPs) in South Africa have for the most part been banned, except dichlorodiphenyltrichloroethane (DDT) which is still used as malaria vector control. The aim of this study was to determine OCP residues in the aquatic fauna of one of South Africa's most populated areas, Soweto. Risk to human health through OCP exposure via fish consumption was investigated. Clarias gariepinus was chosen as bioindicator because it is an apex predator that is in abundance, but is also a valued food source. Dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), and chlordanes (CHLs) were detected in the fish tissue with the DDTs being the most prevalent at all sites. Of the three locations, Fleurhof, Orlando, and Lenasia, the latter location's fish had the highest ΣOCP load, ranging between 81 and 1190ng/gwm. The DDTs were determined to be from historic use, whereas the CHL levels indicated more recent inputs. Although the possibility of illegal use cannot be excluded completely, the presence of OCPs outside of their allowed areas of use indicate that these compounds not only stay in the aquatic systems long term, but may be of concern in areas previously not considered high risk areas. The OCP residues in C. gariepinus from the study area pose an extremely high risk to human health when consumed, and has a cancer risk as high as 1 in 10. This potential problem should be kept in consideration when developing national health and conservation strategies.

Human Risk Assessment of Organochlorine Pesticide Residues in Vegetables from Kumasi, Ghana

The use of organochlorine pesticides has been banned worldwide due to their toxicities. However, some farmers use them illegally because of their potency. The aim of this study was to assess the level of organochlorine pesticide (OCP) residues and the potential health risk associated with vegetables, soil, and groundwater obtained from farms in Ayigya, Nsenie, Gyenyase, and Kentinkrono in Kumasi, Ghana. A total of 15 samples were analyzed using a gas chromatograph equipped with an electron capture detector. The highest mean concentration of 184.10 ± 12.11 µg/kg was recorded for methoxychlor in cabbage from Ayigya. Beta-hexachlorocyclohexane (beta-HCH) recorded the lowest mean concentration of 0.20 ± 0.00 µg/kg in cabbage from Ayigya. The combined risk index showed significant health risk to children than adults. The soil samples mainly contained methoxychlor followed by dichlorodiphenyltrichloroethane (DDT), aldrin, and other OCPs. Concentrations of total HCHs, total DDTs, and total OCPs in the soil samples ranged from <0.01 to 49.00, <0.01 to 165.81, and <0.01 to 174.91 µg/kg, respectively. Among all HCH and DDT isomers, only β-HCH and p,p′-DDT were detected in some of the water samples. Carcinogenic risk values for β-HCH, aldrin, and p,p′ DDT in the groundwater were found to be >10−6, posing a potentially serious cancer risk to consumers. Moreover, the hazard quotients (HQs) of aldrin exceeded the threshold value of one, indicating that daily exposure is a potential concern.

Human Health Risk from Consumption of Marine Fish Contaminated with DDT and Its Metabolites in Maputo Bay, Mozambique

Many countries with incidence of malaria, including those surrounding Maputo Bay, use dichloro-diphenyl-trichloroethane (DDT) to reduce mosquitoes. This study is the first to estimate the human health risk associated with consumption of marine fish from Maputo Bay contaminated with DDTs. The median for ∑DDTs was 3.8 ng/g ww (maximum 280.9 ng/g ww). The overall hazard ratio for samples was 1.5 at the 75th percentile concentration and 28.2 at the 95th percentile. These calculations show increased potential cancer risks due to contamination by DDTs, data which will help policy makers perform a risk-benefit analysis of DDT use in malaria control programs in the region.

Health risk assessment of Chinese consumers to Cadmium via dietary intake

This paper investigated the concentration of Cd in foods via surveys and a literature review. The concentration of Cd in different food groups was in the decreasing order of meat > aquatic products > cereal > vegetable > bean > egg > dairy > fruit. More precisely, on average the weekly Cd intake for men, women, 2-3-year-old children and 4-17-year-old children were 0.0039, 0.0041, 0.0069 and 0.0064mgkg^-1 bw week^-1, respectively. Among all food groups, cereal was the most significant contributor to the dietary intake of Cd, followed by vegetable, aquatic products and meat. For Chinese consumers, the results of risk assessment for all groups by the deterministic method and the probabilistic method showed the mean weekly Cd intake via dietary exposure was lower than the provisional tolerable weekly intake (PTWI) proposed by WHO. However, the 95th and 97.5th percentile THQ values all exceeded 1, and the probability of dietary Cd exposure greater than the weekly intake tolerance (THQ >1) were 15.9%, 17.1%, 42.3% and 28.4% for men, women, 2-3-year-old children and 4-17-year-old children, indicating a potential risk from Cd exposure via dietary intake, especially for children. It appeared that dietary Cd exposure should deserve our attention, and positive measures must be taken to reduce the concentration of Cd in food at once.

The Sources of Chemical Contaminants in Food and Their Health Implications

Food contamination is a matter of serious concern, as the high concentration of chemicals present in the edibles poses serious health risks. Protecting the public from the degrees of the harmfulness of contaminated foods has become a daunting task. This article highlights the causes, types, and health implications of chemical contamination in food. The food contamination could be due to naturally occurring contaminants in the environment or artificially introduced by the human. The phases of food processing, packaging, transportation, and storage are also significant contributors to food contamination. The implications of these chemical contaminants on human health are grave, ranging from mild gastroenteritis to fatal cases of hepatic, renal, and neurological syndromes. Although, the government regulates such chemicals in the eatables by prescribing minimum limits that are safe for human consumption yet measures still need to be taken to curb food contamination entirely. Therefore, a variety of food needs to be inspected and measured for the presence of chemical contaminants. The preventative measures pertaining about the food contaminants problems are pointed out and discussed.

Health risk assessment for the consumption of fresh and preserved fish (Alosa agone) from Lago di Como (Northern Italy)

BACKGROUND

Although banned in many countries for decades, DDTs and PCBs still represent a global threat to food safety. As these contaminants are still present in aquatic ecosystems, fish can be an important contributor to their total dietary intake.

OBJECTIVES

Alosa agone specimens were sampled over a period of 10 years (from 2006 to 2015) to provide a representative overview of the DDT and PCB levels of Lago di Como, a deep Italian lake where a DDT input due to secondary sources was observed in recent years. The potential health risk from the consumption of both fresh and preserved fish was evaluated.

RESULTS

While DDT levels have generally decreased during the monitored period, reaching quite stable levels, PCB concentrations were variable, with values exceeding, in some cases, the European Union limit for human consumption and enabling potential carcinogenic effects. However, typical local processing of this fish species markedly appeared to decrease these contaminant levels, thus making the fish product (called missoltino) a safer food.

CONCLUSIONS

The results of this work highlighted the need of continuous biomonitoring of those contaminants considered a past issue along with the emergent ones.

Association of Dietary Intake and Biomarker Levels of Arsenic, Cadmium, Lead, and Mercury among Asian Populations in the United States: NHANES 2011-2012

BACKGROUND

We have recently shown that biomarker levels of selected metals are higher in Asians than in other U.S. ethnic groups, with important differences within selected Asian subgroups. Much of this difference may be dietary in origin; however, this is not well established.

OBJECTIVE

We evaluated dietary intake of toxic metals as a source of increased biomarker levels of metals among U.S. Asians.

METHODS

We estimated daily food consumption and dietary intake of arsenic, cadmium, lead, and mercury by combining 24-hr dietary intake recall data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) with data from the USDA Food Composition Intake Database and FDA Total Dietary Study. We analyzed associations between dietary metal intake and biomarker levels of the metals using linear regression. Further, estimated food consumption and metal intake levels were compared between Asians and other racial/ethnic groups (white, black, Mexican American, and other Hispanic) and within three Asian subgroups (Chinese, Indian Asian, and other Asians).

RESULTS

Significant associations (p < 0.05) were found between biomarker levels and estimated dietary metal intake for total and inorganic arsenic and mercury among Asians. Asians had the highest daily fish and rice consumption across the racial/ethnic groups. Fish was the major contributor to dietary mercury and total arsenic intake, whereas rice was the major contributor to inorganic arsenic dietary intake. Fish consumption across the Asian subgroups varied, with Asian Indians having lower fish consumption than the other Asian subgroups. Rice consumption was similar across the Asian subgroups.

CONCLUSIONS

We confirmed that estimated dietary intake of arsenic (total and inorganic) and mercury is significantly associated with their corresponding biomarkers in U.S. Asians, using nationally representative data. In contrast, estimated dietary intake of cadmium and lead were not significantly associated with their corresponding biomarker levels in U.S. Asians. Citation: Awata H, Linder S, Mitchell LE, Delclos GL. 2017. Association of dietary intake and biomarker levels of arsenic, cadmium, lead, and mercury among Asian populations in the United States: NHANES 2011-2012. Environ Health Perspect 125:314-323; http://dx.doi.org/10.1289/EHP28.

Comparison of industrial emissions and carpet dust concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in a multi-center U.S. study

Proximity to facilities emitting polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) has been associated with increased risk of non-Hodgkin lymphoma (NHL). There is limited information about whether proximity to industrial sources leads to indoor PCDD/F contamination of homes. We measured carpet dust concentrations (pg/g) of 17 toxic PCDD/F congeners and calculated their toxic equivalence (TEQ) in 100 homes in a population-based case-control study of NHL in Detroit, Los Angeles, Seattle, and Iowa (1998-2000). We took global positioning system readings at residences and obtained coordinates and PCDD/F emissions (ng TEQ/yr) from an Environmental Protection Agency database for 6 facility types: coal-fired electricity generating plants, cement kilns burning non-hazardous waste, hazardous waste incinerators, medical waste incinerators, municipal solid waste incinerators, and sewage sludge incinerators. For each residence, we computed an inverse distance-squared weighted average emission index (AEI [pg TEQ/km2/yr]) for all facilities within 5km from 1983 to 2000. We also computed AEIs for each of the 6 facility types. We evaluated relationships between PCDD/F dust concentrations and the all-facility AEI or categories of facility-type AEIs using multivariable linear regression, adjusting for study center, demographics, and home characteristics. A doubling of the all-facility AEI was associated with a 4-8% increase in PCDD/F dust concentrations of 7 of 17 PCDD/F congeners and the TEQ (p-value<0.1). We also observed positive associations between PCDD/F dust concentrations and facility-type AEIs (highest vs. lowest exposure category) for municipal solid waste incinerators (9 PCDD/F, TEQ), and medical waste incinerators (7 PCDD/F, TEQ) (p<0.1). Our results from diverse geographical areas suggest that industrial PCDD/F emission sources contribute to residential PCDD/F dust concentrations. Our emissions index could be improved by incorporating local meteorological data and terrain characteristics. Future research is needed to better understand the links between nearby emission sources, human exposure pathways, and health risks.

Concentrations of selected persistent organochlorine contaminants in store-bought foods from northern Alaska

OBJECTIVES

We address marine and terrestrial mammal blubber, liver, muscle, kidney, heart, tongue, maktak and maktaaq (epidermis and blubber from bowhead, beluga whales, respectively), and fish muscle and livers, as commonly consumed tissues in subsistence communities across northern Alaska in the context of organochlorine (OC) contamination of store-bought foods. Human exposure to contaminants from biota, as part of a subsistence diet, has been superficially evaluated in numerous studies (focused on liver and blubber), but are limited in the type of tissues analyzed, and rarely consider the contaminants in the alternatives (i.e., store-bought foods).

STUDY DESIGN

Concentrations from published literature on selected persistent organochlorine contaminants (OCs) in eight tissues of the bowhead whale and other biota (1) were compared to store-bought foods evaluated in this study.

RESULTS

As expected, store-bought foods had lower concentrations of OCs than some tissues of the marine mammals (especially blubber, maktak, and maktaaq). However, blubber is rarely eaten alone and should not be used to give consumption advice unless considered as a portion of the food item (i.e., maktak). This study indicates that the store-bought food alternatives have detectable OC concentrations (e.g., < 0.01 to 22.5 ng/g w.w. for hexachlorobenzene) and, in many cases, have greater OC concentrations than some subsistence food items. Many wildlife tissues had OC concentrations similar to those quantified in local store-bought food.

CONCLUSIONS

Switching from the traditional diet to western store-bought foods will not always reduce exposure to OCs. However, raw blubber-based products are clearly more contaminated with OCs due to lipid content. A detailed profile of traditional/country foods and western foods consumed by subsistence communities of northern Alaska is required to address chronic exposure in more detail for the diverse sources of foods (subsistence use and commercially available) and the widely varying concentrations of contaminants reported therein. This should be combined with biomonitoring people dependent upon subsistence foods. Further assessment of essential and non-essential elements, emerging contaminants (e.g. brominated flame retardants), etc. should be conducted in order to improve our understanding of the differences and similarities between wildlife and store-bought foods.