Source Reduction Technologies in California Printed Circuit Board Manufacture

A detailed technical review was made of hazardous waste source reduction technology used by California printed circuit board manufacturers. The purpose of the review was to assess the implementation of hazardous waste source reduction technology available for the printed circuit board manufacturing industry

Source Reduction Technologies in California Printed Circuit Board Manufacture

A detailed technical review was made of hazardous waste source reduction technology used by California printed circuit board manufacturers. The purpose of the review was to assess the implementation of hazardous waste source reduction technology available for the printed circuit board manufacturing industry

Assessment of the Polymers and Resins Industry\u27s Hazardous Waste Source Reduction Planning Efforts

This report summarizes the results of the Department of Toxic Substances Control\u27s (DTSC) assessment of the polymers and resin industry\u27s source reduction planning efforts, as mandated by the Hazardous Waste Source Reduction and Management Review Act of 1989 (Act). The assessment of the polymers and resin industry in California is based upon a review of documents produced by a sample of facilities in the state. It includes infonnation on the sources and types of hazardous waste generated by this industry and describes some of the steps taken to reduce the quantities or hazardous characteristics of waste generated in their operations. In addition, three case studies are featured as practical examples to show how source reduction practices benefited particular facilities

Maternal Low-Level Lead Exposure and Fetal Growth

Background Limited epidemiologic studies have examined the association between maternal low-level lead exposure [blood lead (PbB) \u3c 10 μg/dL] and fetal growth. Objective We examined whether maternal low-level lead exposure is associated with decreased fetal growth. Methods We linked New York State Heavy Metals Registry records of women who had PbB measurements with birth certificates to identify 43,288 mother–infant pairs in upstate New York in a retrospective cohort study from 2003 through 2005. We used multiple linear regression with fractional polynomials and logistic regression to relate birth weight, preterm delivery, and small for gestational age to PbB levels, adjusting for potential confounders. We used a closed-test procedure to identify the best fractional polynomials for PbB among 44 combinations. Results We found a statistically significant association between PbB (square root transformed) and birth weight. Relative to 0 μg/dL, PbBs of 5 and 10 μg/dL were associated with an average of 61-g and 87-g decrease in birth weight, respectively. The adjusted odds ratio for PbBs between 3.1 and 9.9 μg/dL (highest quartile) was 1.04 [95% confidence interval (CI), 0.89–1.22] for preterm delivery and 1.07 (95% CI, 0.93–1.23) for small for gestational age, relative to PbBs ≤ 1 μg/dL (lowest quartile). No clear dose–response trends were evident when all of the quartiles were assessed. Conclusions Low-level PbB was associated with a small risk of decreased birth weight with a supralinear dose–response relationship, but was not related to preterm birth or small for gestational age. The results have important implications regarding maternal PbB

Cadmium pigments in consumer products and their health risks

© 2018 Elsevier B.V. Cadmium is a toxic heavy metal that has been increasingly regulated over the past few decades. The main exposure routes for the general public are the consumption of certain foods and the inhalation of cigarette smoke. However, additional exposure may occur through the current and historical use of the metal in consumer products. In this paper, the uses of Cd in consumer goods are reviewed, with the focus on brightly-coloured Cd sulphide and sulphoselenide pigments, and measurements of Cd in historical and contemporary products ascertained by XRF are reported. Cadmium is encountered across a wide range of contemporary plastic products, mainly because of the unregulated recycling of electronic waste and polyvinyl chloride. However, concentrations are generally low (<100 μg g−1), conforming with current limits and posing minimal risk to consumers. Of greater concern is high concentrations of pigmented Cd (up to 2% by weight) in old products, and in particular children's toys that remain in circulation. Here, tests conducted suggest that Cd migration in some products exceeds the Toy Safety Directive limit of 17 μg g−1 by an order of magnitude. The principal current use of Cd pigments is in ceramic products where the metal is encapsulated and overglazed. Leaching tests on new and secondhand items of hollowware indicate compliance with respect to the current Cd limit of 300 μg L−1, but that non-compliance could occur for items of earthenware or damaged articles should a proposed limit of 5 μg L−1 be introduced. The greatest consumer risk identified is the use of Cd pigments in the enamels of decorated drinking glasses. Thus, while décor is restricted to the exterior, any enamel within the lip area is subject to ready attack from acidic beverages because the pigments are neither encapsulated nor overglazed. Glass bottles decorated with Cd-based enamel do not appear to represent a direct health hazard but have the propensity to contaminate recycled glass products. It is recommended that decorated glassware is better regulated and that old, brightly-coloured toys are treated cautiously

Refinement of arsenic attributable health risks in rural Pakistan using population specific dietary intake values

Background: Previous risk assessment studies have often utilised generic consumption or intake values when evaluating ingestion exposure pathways. If these values do not accurately reflect the country or scenario in question, the resulting risk assessment will not provide a meaningful representation of cancer risks in that particular country/scenario. Objectives: This study sought to determine water and food intake parameters for one region in South Asia, rural Pakistan, and assess the role population specific intake parameters play in cancer risk assessment. Methods: A questionnaire was developed to collect data on sociodemographic features and 24-hour water and food consumption patterns from a rural community. The impact of dietary differences on cancer susceptibility linked to arsenic exposure was evaluated by calculating cancer risks using the data collected in the current study against standard water and food intake levels for the USA, Europe and Asia. A probabilistic cancer risk was performed for each set of intake values of this study. Results: Average daily total water intake based on drinking direct plain water and indirect water from food and beverages was found to be 3.5 L day-1 (95% CI: 3.38, 3.57) exceeding the US Environmental Protection Agency’s default (2.5 L day-1) and World Health Organization’s recommended intake value (2 L day-1). Average daily rice intake (469 g day-1) was found to be lower than in India and Bangladesh whereas wheat intake (402 g day−1) was higher than intake reported for USA, Europe and Asian sub-regions. Consequently, arsenic-associated cumulative cancer risks determined for daily water intake was found to be 17 in children of 3-6 years (95% CI: 0.0014, 0.0017), 14 in children of age 6-16 years (95% CI: 0.001, 0.0011) and 6 in adults of 16-67 years (95% CI: 0.0006, 0.0006) in a population size of 10000. This is higher than the risks estimated using the US Environmental Protection Agency and World Health Organization’s default recommended water intake levels. Rice intake data showed early life cumulative cancer risks of 15 in 10000 for children of 3-6 years (95% CI: 0.0012, 0.0015), 14 in children of 6-16 years (95% CI: 0.0011, 0.0014) and later life risk of 8 in adults (95% CI: 0.0008, 0.0008) in a population of 10000. This is lower than cancer risks in countries with higher rice intake and elevated arsenic levels (Bangladesh and India). Cumulative cancer risk from arsenic exposure showed the relative risk contribution from total water to be51%, from rice to be44% and wheat intake 5%. Conclusions: The study demonstrates the need to use population specific dietary information for risk assessment and risk management studies. Probabilistic risk assessment concluded the importance of dietary intake in estimating cancer risk, along with arsenic concentrations in water or food and age of exposed rural population

Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts

Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007). Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances