Does mortality risk of cigarette smoking depend on serum concentrations of persistent organic pollutants? Prospective investigation of the vasculature in Uppsala seniors (PIVUS) study

Cancer Risk following Residential Exposure to Airborne Polychlorinated Biphenyls: A Danish Register-Based Cohort Study

BACKGROUND

Polychlorinated biphenyls (PCBs) are biopersistent chemicals classified as human carcinogens. This classification is primarily based on evidence on higher-chlorinated PCBs found in food. The carcinogenic potential of airborne lower-chlorinated PCBs remains largely unexplored.

OBJECTIVES

We aimed to investigate cancer risk following residential exposure to airborne PCBs.

METHODS

Cancer risk was examined in the Health Effects of PCBs in Indoor Air (HESPAIR) cohort of 38,613 residents of two partly PCB-contaminated residential areas in Greater Copenhagen, identified by nationwide registries. PCB exposure was based on relocation dates and indoor air PCB measurements in subsets of apartments. Cancer diagnoses were extracted from the Danish Cancer Registry for the follow-up period of 1970-2018. We estimated adjusted hazard ratios with time-varying cumulative exposure and a 10-y lag using Cox regression.

RESULTS

Overall risk of cancer was not associated with PCByear, [hazard ratio (HR) for high-exposed vs. low-exposed =0.98; 95% confidence interval (CI): 0.88, 1.09], but residents exposed to ≥3,000 ng/m3 PCB×year had higher risk of liver cancer (HR =2.81; 95% CI: 1.28, 6.15) and meningiomas (HR =3.49; 95% CI: 1.84, 6.64), with indications of exposure-response relationships. Results were suggestive of a higher risk of pancreatic cancer (HR =1.59; 95% CI: 0.95, 2.64) at the highest aggregated PCB level. For testis cancer, a higher risk was observed among residents exposed to 300-949 ng/m3 PCB×year relative to residents exposed to <300 ng/m3 PCB×year (HR =2.97; 95% CI: 1.41, 6.28), but the risk was not higher for residents exposed to ≥950 ng/m3 PCB×year. Apart from this, the risk of specific cancers was similar across exposure groups.

DISCUSSION

In this, to our knowledge, first population-based cohort study of residential exposure to airborne PCBs, we found no association between exposure to PCBs in indoor air in private homes and the risk for most of the specific cancers. Higher risk of liver cancer and meningiomas were observed. https://doi.org/10.1289/EHP10605.

Associations Between Household Pesticide Exposure, Smoking and Hypertension

This analysis aims to investigate the association between household pesticide exposure and hypertension risk, and to determine whether smoking plays a role in this association. We used data from the National Health and Nutrition Examination Survey (NHANES) for the years 1999–2014, including a total of 32,309 U.S. adult participants who were 20 years or older. Smoking status and pesticide exposure were self-reported. Blood pressure was measured by trained personnel using a mercury sphygmomanometer, according to a standardized protocol. We observed an increased risk of hypertension (OR [odds ratio] = 1.10, 95% confidence intervals [CI]: 1.01–1.18) in participants with exposure to household pesticides. Moreover, a significant interaction between smoking status and pesticide exposure on hypertension was observed (P = 0.022). Stratified analysis showed that household pesticide exposure was associated with a 29% higher risk of hypertension (OR = 1.29, 95% CI: 1.08–1.53) in smokers. However, for non-smokers, this association was not significant. Similar trends were found for systolic and diastolic blood pressures. In addition, we investigated the associations between pesticide metabolites in urine/serum and hypertension and found that several metabolites of dioxins, furans, and coplanar polychlorinated biphenyls were significantly associated with a higher risk of hypertension. This study suggests that household pesticide exposure is associated with an elevated risk of hypertension. We also report that smoking may accentuate the effect of pesticide exposure on hypertension.

Concentrations of nine endogenous steroid hormones in 70-year-old men and women

OBJECTIVES

Circulating concentrations of endogenous steroids have systemic implications on health in elderly. However, population-based age- and ethnicity-specific data are scarce. The aim was to report sex-specific plasma concentrations of endogenous sex and adrenal steroids in elderly Swedish Caucasians, to examine the impact of BMI and to present concentrations in apparently healthy subjects.

METHODS

A population-based observational study of 70-year olds, including 684 community-dwelling men and women enrolled in the PIVUS study, Sweden. Median plasma concentrations were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for pregnenolone, 17-hydroxypregnenolone, 17-hydroxy-progesterone, 11-deoxycortisol, DHEA, androstenedione, testosterone, estrone and estradiol.

RESULTS

Plasma concentrations were significantly higher in men (n = 452) than in women (n = 232) for estradiol: median 61.3 pmol/L (95% CI, 11.4, 142.7) vs 18.4 (4.0, 127.3), for estrone: 92.8 (33.3, 206) vs 71.6 (17.8, 209) pmol/L, and for testosterone 13.8 (5.7, 28.0) vs 0.7 (0.2, 2.0) nmol/L. Higher concentrations of estrone and estradiol were observed in obese than non-obese women. Compared to non-obese men, obese men had lower concentrations of testosterone and its precursors: 17-hydroxypregnenolone, 17-hydroxyprogesterone, androstenedione and DHEA. The subgroup of apparently healthy individuals had median values > 20% lower for estrone and estradiol in women but slightly higher for testosterone in both sexes.

CONCLUSIONS

Concentrations of estradiol, estrone and testosterone were higher in 70-year-old men than in women. BMI associated positively to estradiol and estrone in women and negatively to testosterone in men. Apparently healthy women had lower median concentrations of estradiol and estrone and men had higher median testosterone compared to all individuals.

Association of Exposure to Persistent Organic Pollutants With Mortality Risk: An Analysis of Data From the Prospective Investigation of Vasculature in Uppsala Seniors (PIVUS) Study

IMPORTANCE

It has been suggested that persistent organic pollutants (POPs) are harmful to human health.

OBJECTIVE

To investigate if POP levels in plasma are associated with future mortality.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study using data from the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study, collected between May 2001 and June 2004 when participants reached age 70 years. Participants were followed up for 5 years after the first examination. Mortality was tracked from age 70 to 80 years. Data analysis was conducted in January and February 2018.

EXPOSURES

Eighteen POPs identified by the Stockholm Convention, including polychlorinated biphenyls (PCBs), organochlorine pesticides, and a brominated flame retardant, were measured in plasma levels by gas chromatography-mass spectrometry.

MAIN OUTCOMES AND MEASURES

All-cause mortality.

RESULTS

The study sample initially included 992 individuals (497 [50.1%] men) aged 70 years, who were examined between 2001 and 2004. At the second examination 5 years later, 814 individuals (82.1%; 412 [50.7%] women) completed follow-up. During a follow-up period of 10.0 years, 158 deaths occurred. When updated information on POP levels at ages 70 and 75 years was associated with all-cause mortality using Cox proportional hazard analyses, a significant association was found between hexa-chloro- through octa-chloro-substituted (highly chlorinated) PCBs and all-cause mortality (except PCB 194). The most significant association was observed for PCB 206 (hazard ratio [HR] for 1-SD higher natural log-transformed circulating PCB 206 levels, 1.55; 95% CI, 1.26-1.91; P < .001). Following adjustment for hypertension, diabetes, smoking, body mass index, and cardiovascular disease at baseline, most associations were no longer statistically significant, but PCBs 206, 189, 170, and 209 were still significantly associated with all-cause mortality (PCB 206: adjusted HR, 1.47; 95% CI, 1.19-1.81; PCB 189: adjusted HR, 1.29; 95% CI, 1.08-1.55; PCB 170: adjusted HR, 1.24; 95% CI, 1.02-1.52; PCB 209: adjusted HR, 1.29; 95% CI, 1.04-1.60). In a secondary analysis, these associations were mainly because of death from cardiovascular diseases rather than noncardiovascular diseases. Three organochlorine pesticides, including dichlorodiphenyldichloroethylene, and the brominated flame retardant diphenyl ether 47 were also evaluated but did not show any significant associations with all-cause mortality.

CONCLUSIONS AND RELEVANCE

Higher levels of highly chlorinated PCBs were associated with an increased mortality risk, especially from cardiovascular diseases. These results suggest that public health actions should be undertaken to minimize exposure to highly chlorinated PCBs.

Analysis of spatial distribution of trace metals, PCB, and PAH and their potential impact on human health in Virginian Counties and independent cities, USA

Increasing anthropogenic alteration has resulted in increased exposure to both point and nonpoint source pollution. These exposures are increasingly studied for their role in human diseases, including diseases with known genetic or lifestyle risk factors. This study analyzed associations between a variety of human diseases and trace metals, PCBs, and PAHs in soil, groundwater, sediment, and fish. Contaminant spatial data at the county level from Virginia were used in ArcGIS to identify these associations among socially vulnerable populations. The neurologic and psychiatric disorders and cognitive markers were associated with numerous metals in groundwater/soil and/or aquatic system contaminants. Cancer death rates, fetal deaths, and infant deaths were also related to multiple environmental exposures from both categories of exposure. In contrast, many of the chronic diseases which are primarily attributed to lifestyle showed little association with these exposures with the exception of COPD which did appear to be associated with multiple metal exposures. Asthma showed similar associations compared to COPD. Our data suggest that within the context of socially vulnerable populations, where disease burden is often highest, exposures to metals, PAHs, and PCBs may play a role in the development or exacerbation of several highly prevalent categories of disease. These environmental exposures likely act through a variety of pathways all generally leading to increased oxidative stress, inflammation, or interference with biological systems and a subsequent role in disease development.

Different associations of albuminuria with total and cardiovascular mortality by concentrations of persistent organic pollutants in the elderly

Epidemiologic studies have indicated that albuminuria is associated with mortality from all causes and cardiovascular disease (CVD), with substantial heterogeneity. We evaluated if the associations of urine albumin creatinine ratio (ACR) with all-cause and CVD mortality differed depending on serum concentrations of persistent organic pollutants (POPs), strong lipophilic chemical mixtures with very long half-lives, which are recently linked to many degenerative diseases. Study subjects were participants of the National Health and Nutrition Examination Survey 1999-2004 who were 60 years or older at baseline (n=1215 and 1067 for organochlorine pesticides (OCPs) and other POPs, respectively). They were followed-up through 2011 (mean follow-up periods: 8.1 and 8.0 years for OCPs and other POPs, respectively). The associations between the ACR and all-cause mortality significantly differed by the serum levels of POPs, especially organochlorine pesticides (OCPs; P_interaction<0.01). Stratified analyses indicated that the associations between ACR and all-cause mortality became stronger as the serum levels of OCPs increased. Among the elderly with the highest tertile of OCPs, the adjusted hazard ratios were 1.0, 1.1, and 2.9 (P_trend<0.01) across the categories of ACR (<10, 10-<30, and ≥30mg/g); however, ACR was not clearly related to mortality among the elderly with the lowest tertile of OCPs. CVD mortality showed similar interactions, as noted for all-cause mortality (P_interaction<0.01). The different associations between albuminuria and mortality by the serum OCP levels and the little association among the elderly with low serum OCPs levels suggest that OCPs play an important role in albuminuria-related death risk. However, these findings need to be replicated in other cohort studies.

Hydroxylated polychlorinated biphenyl metabolites (OH-PCBs), maternal smoking and size at birth

In a sample of 442 births from the Child Health and Development Studies cohort, we examined associations between maternal prenatal exposure to hydroxylated polychlorinated biphenyl metabolites (OH-PCBs) and pregnancy outcomes, and whether associations were mediated by maternal thyroid hormone levels and/or modified by maternal smoking. Compared to nonsmokers, smokers had twice the mean concentration of 4-OH-CB107 (p<0.001) and lower levels of its parent compound, PCB118 (p=0.001). Among mothers who smoked, the birth weight of newborns with maternal concentrations of 4-OH-CB107 in the upper quartile was 316g lighter (95% confidence interval (CI) 566, 65) compared to those with maternal concentrations in the lowest quartile, after control for PCB118 and other potential confounders. This association was not observed for non-smoking mothers and was not mediated by maternal thyroid hormone levels. Maternal prenatal 4-OH-CB107 levels appear to be influenced by maternal smoking and contribute to lower birth weight among smokers.

Endocrine-disrupting polychlorinated biphenyls in metabolically healthy and unhealthy obese subjects before and after weight loss: difference at the start but not at the finish

BACKGROUND

A subset of obese individuals does not exhibit metabolically unfavorable features; this group is referred to as metabolically healthy obese (MHO). Serum concentrations of polychlorinated biphenyls (PCBs), which are chemicals with endocrine-disrupting properties, have been shown to be lower in MHO than in metabolically unhealthy obese (MUO).

OBJECTIVE

We studied PCB serum concentrations during and after weight loss and their relation with metabolic health.

DESIGN

We determined metabolic health features (weight, blood pressure, lipids, inflammation, and glucose metabolism) and serum PCB concentrations of 27 PCBs in a cohort of 184 overweight and obese subjects. Metabolic health was evaluated with the use of the criteria of the metabolic syndrome (MetS) [metabolic syndrome according to Adult Treatment Panel III criteria present (MetS+) or metabolic syndrome according to Adult Treatment Panel III criteria absent (MetS−)] or with extended criteria with inflammation and insulin resistance taken into account (MUO compared with MHO). Participants were treated with lifestyle counseling or bariatric surgery. A metabolic and toxicological re-evaluation was performed after 6 and 12 mo.

RESULTS

At baseline, serum ΣPCB concentrations were significantly higher in MUO than in MHO (ΣPCBs: 138 ±105 compared with 365 ± 481 ng/g lipid weight; P = 0.01) but not in MetS+ compared with MetS− subjects. No difference was detected in the percentage increase in PCB serum concentrations in MetS+ compared with MetS− subjects (median: 58% compared with 43% and 31% compared with 69% at 6 and 12 mo, respectively). The comparison of persistent with resolved MetS and MUO did not reveal any difference in ΣPCB concentration increments (median: 49% compared with 58% at 12 mo for MUO; P > 0.05). In a regression model with age, smoking, and body mass index corrected for, PCB serum concentrations at baseline were not predictive of the persistence or resolution of a metabolically unfavorable state.

CONCLUSION

Our study indicates that the increment in serum concentrations of PCBs does not differ according to metabolic health and does not seem to influence the beneficial metabolic health effects of weight loss. This study was registered at clinicaltrials.gov at NCT01778868.