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.

Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m³ of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m³. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

Structural fumigations using sulfuryl fluoride for the extermination of dry-wood termites are conducted by the thousands in California and other warm-weather states. Sulfuryl fluoride is an odorless gas that targets the nervous system and can cause respiratory irritation, pulmonary edema, nausea, vomiting, seizures, and death. Structural voids or compartments such as wall sockets, crawl spaces, cabinets, or cells in air mattresses may create ongoing exposure after a structure has been certified as safe. The authors describe a case of potential sulfuryl fluoride exposure to a family following home fumigation. Despite regulation, sulfuryl fluoride poisonings from structural fumigations continue to occur. This article examines the physical characteristics of sulfuryl fluoride and the regulatory oversight of its application, in an effort to understand how and why these poisonings happen. Increasing aeration times of fumigated structures, overseeing monitoring efficacy, and using technology to capture clearance data could reduce sulfuryl fluoride exposure and illness.

Background: Thallium is a metal that is ubiquitous in our natural environment. Despite its potential for high toxicity, thallium is understudied and not regulated in food. The California Department of Public Health was alerted to a household cluster of elevated urine thallium levels noted among a mother (peak 5.6 µg/g creatinine; adult reference: ≤0.4 µg/g creatinine) and her three young children (peak 10.5 µg/g creatinine; child reference: ≤0.8 µg/g creatinine). Objectives: This case report identifies questions raised after a public health investigation linked a household’s thallium exposure to a commercially available food product. We provide an overview of the public health investigation. We then explore concerns, such as gaps in toxicological data and limited surveillance of thallium in the food supply, which make management of individual and population exposure risks challenging. Methods: We highlight findings from a cross-agency investigation, including a household exposure survey, sampling of possible environmental and dietary exposures (ICP-MS analysis measured thallium in kale chips at 1.98 mg/kg and 2.15 mg/kg), and monitoring of symptoms and urine thallium levels after the source was removed. We use regulatory and research findings to describe the challenges and opportunities in characterizing the scale of thallium in our food supply and effects of dietary exposures on health. Discussion: Thallium can bioaccumulate in our food system, particularly in brassica vegetables like kale. Thallium concentration in foods can also be affected by manufacturing processes, such as dehydration. We have limited surveillance data nationally regarding this metal in our food supply. Dietary reviews internationally show increased thallium intake in toddlers. Limited information is available about low-dose or chronic exposures, particularly among children, although emerging evidence shows that there might be risks associated at lower levels than previously thought. Improved toxicological studies are needed to guide reference doses and food safety standards. Promising action towards enhanced monitoring of thallium is being pursued by food safety agencies internationally, and research is underway to deepen our understanding of thallium toxicity.

Public complaints have raised concerns that some mattresses in the current marketplace may be potential sources of airborne fiberglass. Although mattress foam is often marketed as chemical-free, their cover compositions are not as well understood by the general public. To fill these basic information gaps, the covers of four newly purchased mattresses were sampled and analyzed using polarized light microscopy, SEM-EDS, and FTIR microspectroscopy. Two of the mattress covers contained over 50% fiberglass in their inner sock layers. Up to 1% of the fiberglass had migrated to adjacent fabric layers, representing a potential risk of consumer exposure if the zipper on the outer cover is opened. The observed fiberglass fragments had calculated aerodynamic diameters ranging between 30 and 50 µm, suggesting they are potentially inhalable into the nose, mouth, and throat, but are likely too large to penetrate deeper into the lungs. No fiberglass was observed on the brand new mattresses’ outer surfaces. Synthetic fibers also present in the sock layers were consistent with flame resistant modacrylic containing vinyl chloride and antimony. The use of fiberglass and other chemicals in mattress covers poses a potential health risk if these materials are not adequately contained. The apparent non-inclusion of mattress covers in chemical-free certifications suggests that further improvements are needed in mattress labeling and education of consumers.