Hair relaxers have been suggested as a source of exposure to parabens and phthalates. However, dermally absorbed doses of these chemicals resulting from consumer use of hair relaxers have yet to be quantified, and results from epidemiological studies have consistently demonstrated that there is no increased risk for hormone-sensitive, reproductive cancers associated with use of hair relaxers among Black women. Therefore, dermal absorption of parabens and phthalates associated with hair relaxer use for several commercially available hair relaxer kits was modeled using IH SkinPerm™.
View Article and Find Full Text PDFThis analysis updates two previous analyses that evaluated the exposure-response relationships for lung cancer and mesothelioma in chrysotile-exposed cohorts. We reviewed recently published studies, as well as updated information from previous studies. Based on the 16 studies considered for chrysotile (<10% amphibole), we identified the "no-observed adverse effect level" (NOAEL) for lung cancer and/or mesothelioma; it should be noted that smoking or previous or concurrent occupational exposure to amphiboles (if it existed) was not controlled for.
View Article and Find Full Text PDFRegul Toxicol Pharmacol
October 2023
Propylene dichloride (PDC) is a chlorinated substance used primarily as an intermediate in basic organic chemical manufacturing. The United States Environmental Protection Agency (EPA) is currently evaluating PDC as a high-priority substance under the Toxic Substances Control Act (TSCA). We conducted a systematic review of the non-cancer and cancer hazards of PDC using the EPA TSCA and Integrated Risk Information System (IRIS) frameworks.
View Article and Find Full Text PDFInhalation exposure to cosmetic talc has generated much scientific debate regarding its potential as a risk factor for mesothelioma, a rare, but fatal cancer. Barbers, hairdressers, and cosmetologists have regularly used cosmetic talc-containing products, but the collective epidemiological evidence for mesothelioma in these occupations has yet to be described. As such, we conducted a systematic review of PubMed and the National Institute for Occupational Safety and Health's (NIOSH) Numbered Publications list to identify original epidemiological literature reporting measures of association between these occupations and incidence of or death from mesothelioma.
View Article and Find Full Text PDFOccupational exposure limits (OELs) have been previously proposed for diacetyl; however, most of these values are based on worker cohort studies that are known to have several limitations and confounders. In this analysis, an 8 hour time-weighted average (TWA) OEL for diacetyl was derived based on data from a chronic, 2 year animal inhalation study recently released by the US National Toxicology Program. In that study, complete histopathology was conducted on male and female mice and rats exposed to 0, 12.
View Article and Find Full Text PDFFormaldehyde emissions from two laminate flooring products, labeled as California Air Resources Board (CARB) compliant, were evaluated. Passive 24-hr samples (n = 79) and real-time measurements were collected following installation and removal of the products in two rooms of similar size. Mean formaldehyde concentrations following installation were 0.
View Article and Find Full Text PDFThere are currently no published empirical data that characterize hand-to-mouth transfer efficiencies for metallic lead. The purpose of this study was to quantify the hand-to-mouth transfer efficiency of lead in adult volunteers (n = 6) using human saliva as a surrogate for the mouth and commercially available, 100% lead fishing weights as the source of lead for dermal loading. Study volunteers' saliva was collected and subsequently poured onto a sheet of wax paper placed on a balance scale.
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