Abstract  A practical guide to both general principles and specific methods used to assess exposure to indoor air pollutants. Addressed to public health professionals who lack specialized training in this field, the book aims to facilitate well-designed assessments in order to identify health hazards and support strategies for risk management. Information is specific to the assessment of air pollution exposure in such indoor environments as homes, offices, and various public service buildings. The book has two part. The first, which serves as a general introduction, opens with an explanation of concepts used in exposure assessment and important to the design and interpretation of findings. Against this background, subsequent chapters describe specific direct and indirect methods of exposure assessment, and use the example of volatile organic compounds to show how exposure to mixtures can be measured. Other chapters discuss the influence of temperature and humidity on the indoor environment, provide guidelines for the design of exposure assessment surveys, and discuss the components of quality control. The second and most extensive part describes currently available methods for assessing six gaseous air pollutants, four categories of particulate air pollutants, and three biological contaminants commonly found in indoor environments and representing distinct methodological problems. Each pollutant is covered according to a common format which includes information on health effects, sources, variation of exposure, and the advantages and disadvantages of methods for assessing exposure. Further practical guidance is provided in an annex, which includes short summaries of exposure assessment studies completed or under way in the USA and several European countries.

Abstract  Oak Ridge High School is located at 1120 Harvard Way in El Dorado Hills, California, about 30 miles northeast of Sacramento, in El Dorado County. Naturally occurring asbestos has been identified in rocks and soils on and around school property, and a vein of asbestos was disturbed during construction of a soccer field in 2002. A community member, who had been active for several years in voicing concern over asbestos exposures in the area, asked the Agency for Toxic Substances and Disease Registry (ATSDR) to evaluate the public health implications of current and past asbestos exposures of students and staff at the high school. In this public health consultation, ATSDR reviews available environmental data and potential exposure pathways to determine whether adverse health effects are possible from past or present asbestos exposure at Oak Ridge High School and recommends actions to prevent, reduce, or further identify the possibility for adverse health effects. ATSDR has also received numerous reports of health-related concerns about the area surrounding the high school and other areas with naturally occurring asbestos. The US Environmental Protection Agency (EPA) is currently collecting and analyzing data on asbestos levels in other areas of El Dorado County, and ATSDR will address those pathways in a subsequent health consultation.

Abstract  Information was gathered from Federal and State health, labor, and environmental agencies, as well as from groups with special concerns regarding the incidences of impaired health and safety to family members resulting from exposure to hazardous substances found at the workplace of another family member. Workers have been found to inadvertently carry home hazardous materials on their clothes, skin, hair, tools, and in their vehicles. Some of the resulting health effects reviewed in the report include chronic beryllium (7440417) disease, asbestosis and mesothelioma, lead (7439921) poisoning, neurological effects and mental retardation caused by lead exposure, deaths and neurological effects from pesticide exposure, chemical burns from caustic substances, chloracne and other effects from chlorinated hydrocarbon exposure, neurological effects from mercury (7439976), abnormal development from estrogenic substances, asthmatic and allergic reactions from dusts, liver angiosarcoma from arsenic (7440382), dermatitis from fibrous glass, status epilepticus from chemical exposure, and diseases from infectious agents.

Abstract  Heavy sediment loads in the Sumas River of Whatcom County, Washington, increase seasonal turbidity and cause locally acute sedimentation. Most sediment in the Sumas River is derived from a deep-seated landslide of serpentinite that is located on Sumas Mountain and drained by Swift Creek, a tributary to the Sumas River. This mafic sediment contains high amounts of naturally occurring asbestiform chrysotile. A known human-health hazard, asbestiform chrysotile comprises 0.25–37 percent, by mass, of the total suspended sediment sampled from the Sumas River as part of this study, which included part of water year 2011 and all of water years 2012 and 2013. The suspended-sediment load in the Sumas River at South Pass Road, 0.6 kilometers (km) downstream of the confluence with Swift Creek, was 22,000 tonnes (t) in water year 2012 and 49,000 t in water year 2013. The suspended‑sediment load at Telegraph Road, 18.8 km downstream of the Swift Creek confluence, was 22,000 t in water year 2012 and 27,000 t in water year 2013. Although hydrologic conditions during the study were wetter than normal overall, the 2-year flood peak was only modestly exceeded in water years 2011 and 2013; runoff‑driven geomorphic disturbance to the watershed, which might have involved mass wasting from the landslide, seemed unexceptional. In water year 2012, flood peaks were modest, and the annual streamflow was normal. The fact that suspended-sediment loads in water year 2012 were equivalent at sites 0.6 and 18.8 km downstream of the sediment source indicates that the conservation of suspended‑sediment load can occur under normal hydrologic conditions. The substantial decrease in suspended-sediment load in the downstream direction in water year 2013 was attributed to either sedimentation in the intervening river reach, transfer to bedload as an alternate mode of sediment transport, or both. The sediment in the Sumas River is distinct from sediment in most other river systems because of the large percentage of asbestiform chrysotile in suspension. The suspended sediment carried by the Sumas River consists of three major components: (1) a relatively dense, largely non-flocculated material that settles rapidly out of suspension; (2) a lighter component containing relatively high proportions of flocculated material, much of it composed of asbestiform chrysotile; and (3) individual chrysotile fibers that are too small to flocculate or settle out, and remain in suspension as wash load (these fibers are on the order of microns in length and tenths of microns in diameter). Whereas the bulk density of the first (heaviest) component of suspended sediment was between 1.5 and 1.6 grams per cubic centimeter (g/cm3), the bulk density of the flocculated material was an order of magnitude lower (0.16 g/cm3), even after 24 hours of settling. Soon after immersion in water, the fresh chrysotile fibers derived from the Swift Creek landslide seem to flocculate readily into large bundles, or floccules, that exhibit settling velocities characteristic of coarse silts and fine sands (30 and 250 micrometers). In quiescent water within this river system, the floccules settle out quickly, but still leave between 2.4 and 19.5 million chrysotile fibers per liter in the clear overlying water. Consistent with the results from previous laboratory research, the amounts of asbestiform chrysotile in the water column in Swift Creek, as well as in the Sumas River close to and downstream of its confluence with Swift Creek, were determined to be directly correlated with pH. This observation offers a possible alternative to either turbidity or suspended‑sediment concentration as a surrogate for the concentration of fresh asbestiform chrysotile in suspension. Continued movement and associated erosion of the landslide through mass wasting and runoff will maintain large sediment loads in Swift Creek and in the Sumas River for the foreseeable future. Given the present channel morphology of the river system, aggradation (that is, sediment accumulation) in Swift Creek and the Sumas River are also likely to continue.