TagLead(26)

This 2002 draft document presents 1996 modeled air exposure concentration estimates for toxic pollutants including lead, manganese, and arsenic across all U.S. states. It compares statewide source contributions from major industrial areas, onroad vehicles, nonroad sources, and background levels. Supplementary 2001 monitoring data from Sea-Tac Airport and nearby Seattle sites shows measured concentrations of these pollutants, with some local readings—such as a single manganese measurement exceeding 36 ng/m³ and an arsenic reading surpassing 12 ng/m³—notably higher than regional averages.

A soil contamination study by Washington State's Department of Ecology and Public Health – Seattle & King County found elevated levels of arsenic and lead in southern King County soils, linked primarily to the former Asarco smelter in Ruston. Contamination levels were highest near the smelter and on Vashon and Maury Islands, with concentrations decreasing further from the source and following prevailing wind patterns. While the findings are a concern rather than an emergency, officials stress that the study reflects regional trends only and cannot predict contamination levels at individual properties.

Response to Comment #16 by David DeForest to Linda Logan (September 2001) critiquing Shephard (1999) tissue screening concentrations (TSCs) for lead (0.32 mg/kg dw) and zinc (100 mg/kg dw) as applied to cutthroat trout from Miller Creek. Argues Shephard TSCs derived from EPA water quality criteria and bioconcentration factors (BCFs) are not appropriate for cutthroat

This technical memo evaluates whether lead and zinc levels found in cutthroat trout from Miller Creek pose a risk, arguing that standard tissue screening concentrations are not appropriate for trout. Using fish-specific toxicity data and bioconcentration factors, the authors derive alternative thresholds and conclude that measured metal levels in the trout fall well below harmful concentrations. The document recommends using species-specific methods rather than generic screening values when assessing metal risks to fish.