Cancer and Non-Cancer Risk Concerns from Metals in Electronic Cigarette Liquids and Aerosols.

We evaluated metal concentrations in e-liquids and e-aerosols from eight studies and estimated the range of corresponding cancer and non-cancer risks. Chromium and nickel were the leading contributors to cancer risk, with minor contributions from cadmium, lead, and arsenic. The increased cancer risks, assuming exposure to 2 mL/day, ranged from 5.7 to 30,000 additional cancers in a million e-cigarette users. The average cancer risk was 3 in 1000. Cancer risks in the mid to upper end of these ranges exceed acceptable levels. The hazard quotient (HQ) approach was used to evaluate non-cancer risks. Hazard quotients exceeding 1.0 indicate the possibility for non-cancer adverse health effects. Estimated exposures at the maximum reported concentrations of nickel, chromium, and manganese resulted in HQ values of 161, 1.1, and 1.0, respectively, with additional contributions from lead. The average concentration of nickel resulted in an HQ value of 14. We conclude from these studies that exposure to metals in e-cigarette liquids and aerosols may pose a significant cancer and non-cancer health risk at the mid and upper end of the reported ranges. The device design and heating elements appear to be the main source of metals in e-aerosols. The large range of metals within and across e-cigarette brands indicate the need for improvements in product design, enforced product safety regulations and manufacturing quality control. Implementation of such measures could reduce metal exposure in e-cigarette users.

Exposures to environmental phenols in Southern California firefighters and findings of elevated urinary benzophenone-3 levels.

Firefighters are at increased risk for exposure to toxic chemicals compared to the general population, but few studies of this occupational group have included biomonitoring. We measured selected phenolic chemicals in urine collected from 101 Southern California firefighters. The analytes included bisphenol A (BPA), triclosan, benzophenone-3 (BP-3), and parabens, which are common ingredients in a range of consumer products. BP-3, BPA, triclosan, and methyl paraben were detected in almost all study subjects (94-100%). The BP-3 geometric mean for firefighters was approximately five times higher than for a comparable National Health and Nutrition Examination Survey (NHANES) subgroup. Demographic and exposure data were collected from medical records and via a questionnaire, and covariates were examined to assess associations with BP-3 levels. BP-3 levels were elevated across all firefighter age groups, with the highest levels observed in the 35 to 39year old group. Body fat percentage had a significant inverse association with BP-3 concentrations. Our results indicate pervasive exposure to BP-3, BPA, triclosan, and methyl paraben in this population of firefighters, consistent with studies of other populations. Further research is needed to investigate possible explanations for the higher observed BP-3 levels, such as occupational or California-specific exposures.

High exposure of California firefighters to polybrominated diphenyl ethers.

Concern about persistent organic pollutants (POPs) in Californians prompted the state's biomonitoring program to conduct a study in firefighters, who are occupationally exposed to high levels of POPs. In this work we present serum concentrations of several classes of POPs (polybrominated diphenyl ethers [PBDEs], polychlorinated biphenyls [PCBs], and organochlorine pesticides [OCPs]) in 101 Southern California firefighters. Despite recently reported declining trends of PBDEs in Californians, high levels were measured in firefighters' serum (Σ5PBDEs: median = 59.1 ng/(g of lipid); range = 18.8-714 ng/(g of lipid)) in comparison to other populations in California during the same period. In addition, nearly one-third of subjects had particularly high serum levels of decabromodiphenyl ether (BDE-209), consistent with other recent results in firefighters; this pattern may be a marker of recent firefighting activity. In contrast, serum levels of PCBs and OCPs measured in firefighters' sera were not elevated compared to U.S. levels. Multivariable analysis indicated that lower levels of serum PBDEs were associated with turnout gear cleaning and storage practices after fires. Our study supports the hypothesis that firefighting activities are likely to increase exposure to PBDEs and that good housekeeping and personal hygiene practices may reduce exposure to these compounds.

Predictors of tetrabromobisphenol-A (TBBP-A) and hexabromocyclododecanes (HBCD) in milk from Boston mothers.

Tetrabromobisphenol-A (TBBP-A) and hexabromocyclododecanes (HBCDs) are brominated flame retardants that have been found in human milk and serum throughout the world, but have received comparatively little attention in the United States. The objective of this study is to determine concentrations of these analytes in samples of breast milk collected from first-time mothers in the Greater Boston, Massachusetts area and to explore predictors of exposure. Human milk samples were analyzed by LC-ESI-MS/MS for TBBP-A, HBCDs (the α, ß, and γ diastereomers), and HBCD degradation products: pentabromocyclododecanes (PBCDs) and tetrabromocyclododecadienes (TBCDs). HBCD diastereomers were detected in all samples with α-HBCD present in the highest proportion. TBBP-A, PBCDs, and TBCDs were detected in 35%, 42%, and 56% of the analyzed samples, respectively. Self-reported demographic, dietary and behavioral data were examined as predictors of HBCD levels. Levels of HBCD were significantly, positively associated with the number of stereo and video electronics in the home (17% increase/item; 95% Confidence Interval (CI) = 4-31%) and reduced in participants who regularly chose organic foods compared to those who did not (0.51, 95% CI = 0.32-0.82). These results suggest that lifestyle factors are related to body burdens of HBCD and that domestic electronics may be an important source of HBCD exposure in the indoor environment.

Integrated and first trimester prenatal screening in California: program implementation and patient choice for follow-up services.

OBJECTIVES: The California Prenatal Screening Program serves over 350,000 women annually. This study examines utilization rates for the various screening options and patient choices regarding follow-up services. METHODS: The study tracked patients with first trimester positive results for Down syndrome to examine patient decisions regarding follow-up services and/or additional screening and to identify determinants of patient decisions. For first trimester screen positive women who elected further screening, second trimester integrated screening results were analyzed. The Genetic Disease Screening Program Chromosome Registry was used to identify Down syndrome cases. RESULTS: Ethnicity, but not age, was a strong predictor of acceptance of prenatal diagnosis. Approximately 47% of first trimester screen positive women opted for further screening. Among these women, 46% percent received an integrated screen negative result. All but one confirmed Down syndrome case in this cohort were still screen positive. CONCLUSIONS: Data from the California Prenatal Screening Program indicate that all of the major screening modalities continue to be utilized. The wide range of choices made by women with screen positive results demonstrate the importance of including multiple options within the Program. Providing integrated screening to first trimester Down syndrome screen positive women reduced the number of unnecessary invasive procedures.

Practitioner-specific medians for nuchal translucency to improve first-trimester screening performance.

OBJECTIVE: Nuchal translucency medians are used to convert nuchal translucency measurements to multiple of the median values for use in risk assessment. There has been much debate about the use of practitioner-specific medians instead of population-based medians to correct for practitioner bias. This study examined data from the California Prenatal Screening Program to evaluate the effect of individual medians on screening performance. METHODS: For this retrospective study, we identified first-trimester specimens in the California Prenatal Screening Program database for which screening results were calculated using a practitioner-specific median (n=55,286) and recalculated risk assessment using a population-based median. We looked at positive rates for Down syndrome and Trisomy 18 as well as overall screening results. We also looked at the recalculated risks for cases in which there has been a positive diagnosis of a chromosomal abnormality to determine if cases would have been missed if practitioner-specific medians had not been used. RESULTS: Nuchal translucency multiples of the median would be lower for the majority of nuchal translucency practitioners if a population-based median were used instead of practitioner-specific medians. Outcomes data from the California Prenatal Screening Program's database indicate that 14 positively diagnosed cases would have been missed by the screening program if population-based medians had been used. CONCLUSION: The use of practitioner-specific medians corrects for practitioner bias in measuring nuchal translucency. Practitioner-specific medians improve screening performance and help meet detection rate goals. LEVEL OF EVIDENCE: II.

Participant experiences in a breastmilk biomonitoring study: a qualitative assessment.

BACKGROUND: Biomonitoring studies can provide information about individual and population-wide exposure. However they must be designed in a way that protects the rights and welfare of participants. This descriptive qualitative study was conducted as a follow-up to a breastmilk biomonitoring study. The primary objectives were to assess participants' experiences in the study, including the report-back of individual body burden results, and to determine if participation in the study negatively affected breastfeeding rates or duration. METHODS: Participants of the Greater Boston PBDE Breastmilk Biomonitoring Study were contacted and asked about their experiences in the study: the impact of study recruitment materials on attitudes towards breastfeeding; if participants had wanted individual biomonitoring results; if the protocol by which individual results were distributed met participants' needs; and the impact of individual results on attitudes towards breastfeeding. RESULTS: No participants reported reducing the duration of breastfeeding because of the biomonitoring study, but some responses suggested that breastmilk biomonitoring studies have the potential to raise anxieties about breastfeeding. Almost all participants wished to obtain individual results. Although several reported some concern about individual body burden, none reported reducing the duration of breastfeeding because of biomonitoring results. The study literature and report-back method were found to mitigate potential negative impacts. CONCLUSION: Biomonitoring study design, including clear communication about the benefits of breastfeeding and the manner in which individual results are distributed, can prevent negative impacts of biomonitoring on breastfeeding. Adoption of more specific standards for biomonitoring studies and continued study of risk communication issues related to biomonitoring will help protect participants from harm.

Human exposure to PBDEs: associations of PBDE body burdens with food consumption and house dust concentrations.

This study was designed to determine the body burden of polybrominated diphenyl ethers (PBDEs) among first-time mothers in the Greater Boston, Massachusetts area and to explore key routes of exposure. We collected breast milk samples from 46 first-time mothers, 2-8 weeks after birth. We also sampled house dust from the homes of a subset of participants by vacuuming commonly used areas. Data on personal characteristics, diet, home furniture, and electrical devices were gathered from each participant using a questionnaire. Breast milk and dust samples were analyzed for PBDEs using gas chromatography/ mass spectrometry. PBDE concentrations were log-normally distributed in breast milk and dust. We found statistically significant, positive associations between PBDE concentrations in breast milk and house dust (r = 0.76, p = 0.003, not including BDE-209), as well as with reported dietary habits, particularly the consumption of dairy products (r = 0.41, p = 0.005) and meat (r = 0.37, p = 0.01). Due to low detection rates, it was not possible to draw conclusions about the association between BDE-209 in milk and dust. Our results support the hypothesis that the indoor environment and diet both play prominent roles in adult human exposure to PBDEs.