Concentrations of 45 Per- and Polyfluoroalkyl Substances in North American River Otters (Lontra canadensis) from West Virginia, USA.

North American river otters (Lontra canadensis) are top predators in riverine ecosystems and are vulnerable to per- and polyfluoroalkyl substance (PFAS) exposure. Little is known about the magnitude of exposure and tissue distribution of PFAS in river otters. We measured 45 PFAS in various tissues of 42 river otters collected from several watersheds in the state of West Virginia, USA. The median concentrations of ∑All (sum concentration of 45 PFAS) varied among tissues in the following decreasing order: liver (931 ng/g wet weight) > bile > pancreas > lung > kidney > blood > brain > muscle. Perfluoroalkylsulfonates (PFSAs) were the predominant compounds accounting for 58-75% of the total concentrations, followed by perfluoroalkyl carboxylates (PFCAs; 21-35%). 8:2 fluorotelomer sulfonate (8:2 FTS), 10:2 FTS, and 6:2 chlorinated polyfluoroalkyl ether sulfonate were frequently found in the liver (50-90%) and bile (96-100%), whereas hexafluoropropylene oxide dimer acid (HFPO-DA) was rarely found. The hepatic concentrations of ∑All in river otters collected downstream of a fluoropolymer production facility located along the Ohio River were 2-fold higher than those in other watersheds. The median whole body burden of ∑All was calculated to be 1580 µg. PFOS and perfluorooctanoic acid (PFOA) concentrations in whole blood of some river otters exceeded the human toxicity reference values, which warrant further studies.

An exposure assessment of 27 quaternary ammonium compounds in pet dogs and cats from New York State, USA.

Benzylalkyldimethylammonium (BACs), dialkyldimethylammonium (DDACs), and alkyltrimethylammonium compounds (ATMACs) are quaternary ammonium compounds (QACs) used widely as biocides, disinfectants, and sanitizers. Owing to their toxicity, human exposure to this class of chemicals is a concern. Pet animals are sentinels of human exposure to several indoor environmental chemicals. For the first time, we measured 7 BACs, 6 DDACs, 6 ATMACs, and 8 metabolites of BACs in urine and feces of pet dogs and cats from New York State, USA. We found widespread occurrence of QACs in feces, with median concentration of ∑All (sum concentration of all 27 QAC analytes) at 9680 and 1260 ng/g dry weight (dw) in dog and cat feces, respectively. BACs were the most abundant compounds among the four types of QACs, accounting for 64 % and 57 % of ∑All in dog and cat feces, respectively, followed by DDACs (33 % and 34 %, respectively), ATMACs (4 % and 9 %, respectively), and BAC metabolites (0.2 % and 0.3 %, respectively). However, in urine, only ω-carboxylic acid metabolites of BACs were found at median concentrations at 2.08 and 0.28 ng/mL in dogs and cats, respectively. Samples collected from animal shelters contained elevated levels of QACs than those from homes of pet owners. A significant positive correlation was found among the four types of QACs analyzed, which suggested usage of these chemicals in combination as mixtures. Based on the concentrations measured in feces, and through a reverse dosimetry approach, the median cumulative daily intakes (CDIs) of QACs were estimated to be 49.4 and 4.75 µg/kg body weight (BW)/day for dogs and cats, respectively. This study provides first evidence that pet dogs and cats are exposed to QACs at significant levels that warrant further attention.

Occurrence of and dermal exposure to benzene, toluene and styrene found in hand sanitizers from the United States.

Human exposure to carcinogenic volatile organic compounds (VOCs), such as benzene, from hand sanitizers is a topic of current concern. In light of the heavy use of hand sanitizers during the COVID-19 pandemic, determination of exposure to toxicants present in these products deserves attention. The US Food and Drug Administration (FDA) had set an interim limit for benzene in alcohol-based hand sanitizers at 2000 parts-per-billion (ppb). We determined the concentrations of and exposure to three VOCs namely, benzene, toluene and styrene, in 200 hand sanitizers using high-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC-HRMS). Benzene, toluene and styrene were found in 31%, 25% and 32%, respectively, of the samples analyzed at mean concentrations of 395 (range: 0.181-22,300), 164 (range: 0.074-20,700) and 61.3 ng/g (range: 0.082-4200 ng/g), respectively. Benzene was found at concentrations > 2000 ng/g (above the FDA interim limit) in 5% of the samples, representing 9 brands. The mean potential dermal exposure doses (DEDs) to benzene (children/teenagers: 34.6; adults: 24.7 ng/kg-bw/d) were higher than those for toluene (children/teenagers: 14.4; adults: 10.3 ng/kg-bw/d) and styrene (children/teenagers: 5.37; adults: 3.83 ng/kg-bw/d) in the 200 hand sanitizers analyzed. The estimated cancer risk from exposure to benzene in children/teenagers and adults from hand sanitizer use (at an estimated usage rate of 5 g/day) was greater than the one-in-a-million risk benchmark (1.0 × 10-6) for 10% and 9% of the samples, respectively. To the best of our knowledge, this is the first study to determine both the concentrations of and exposure risks to benzene, toluene and styrene present in hand sanitizers.