Causes of unintentional deaths from carbon monoxide poisonings in California.

The purpose of this study was to determine the annual number and incidence of unintentional deaths from carbon monoxide (CO) poisonings in California and to identify specific factors that caused or contributed to the deaths. Unintentional CO deaths in California over a ten-year period (1979 to 1988) were identified from the database of the California Master Mortality File and coroners' investigation reports. Factors associated with unintentional CO deaths were determined based on the information from the investigation reports. The annual number of unintentional CO deaths varied from 27 to 58 over the ten years examined, with an average annual death incidence of 1.7 x 10(-6). Death rates were high among males and African-Americans. Alcohol appeared to be a factor in 31% of the cases. The types of combustion sources associated with unintentional CO deaths were: heating or cooking appliances; motor vehicles; charcoal grills and hibachis; small engines; and camping equipment. Factors associated with unintentional CO deaths interact in a complex way. To reduce the rate of unintentional CO deaths effectively, joint efforts involving several prevention methods are suggested.

Unintentional carbon monoxide deaths in California from charcoal grills and hibachis.

This study was carried out to determine the annual incidence rate of and factors associated with unintentional deaths due to carbon monoxide (CO) poisoning from charcoal grills/hibachis in California during 1979-1988. A search through the California Master Mortality File was conducted to identify all cases with ICD-9 codes related to unintentional CO deaths. Individual coroners' investigation reports were obtained from 42 counties and evaluated by three evaluators. After excluding miscoded and misclassified cases, 444 deaths were judged to be authentic cases of unintentional CO poisoning. Among them, 59 deaths found to be due to the improper use of charcoal grills/hibachis. An increasing but not statistically significant trend was observed over the 10-year period. The highest rates occurred among males, asians, blacks, and middle-aged (20-39) people. Fifty-four percent of the deaths occurred in motor vehicles and 46% in residential structures.

Annual average radon concentrations in California residences.

A study was conducted to determine the annual average radon concentrations in California residences, to determine the approximate fraction of the California population regularly exposed to radon concentrations of 4 pCi/l or greater, and to the extent possible, to identify regions of differing risk for high radon concentrations within the state. Annual average indoor radon concentrations were measured with passive (alpha track) samplers sent by mail and deployed by home occupants, who also completed questionnaires on building and occupant characteristics. For the 310 residences surveyed, concentrations ranged from 0.10 to 16 pCi/l, with a geometric mean of whole-house (bedroom and living room) average concentrations of 0.85 pCi/l and a geometric standard deviation of 1.91. A total of 88,000 California residences (0.8 percent) were estimated to have radon concentrations exceeding 4 pCi/l. When the state was divided into six zones based on geology, significant differences in geometric mean radon concentrations were found between several of the zones. Zones with high geometric means were the Sierra Nevada mountains, the valleys east of the Sierra Nevada, the central valley (especially the southern portion), and Ventura and Santa Barbara Counties. Zones with low geometric means included most coastal counties and the portion of the state from Los Angeles and San Bernardino Counties south.

Volatile organic compounds and building bake-out.

VOCs are generally present in indoor air at concentrations greater than, and not infrequently much greater than, those of outdoor air. These VOCs cover a broad spectrum of compounds, ranging from about 20 to several hundred in any given sample of indoor air. However, the concentrations observed in nonindustrial indoor air samples are generally much lower than occupational health standards. Still, the sources of VOCs indoors are varied and ubiquitous, and the health effects of exposure to VOC are varied and range from irritant effects associated with SBS, to carcinogenic and reproductive effects. A recent study of the health effects of exposure to low concentrations of VOCs has produced surprising results and insight into some of the more subtle health effects. However, additional study is needed to confirm these effects. Many general techniques for mitigating exposures to VOCs are available; the difficulty lies in obtaining the specific information necessary to apply these techniques effectively to a given problem. In some cases this information relates to diagnostics, either to the cause of particular symptoms in individuals or about the particular source or sources of VOCs. In other cases, this information is related to the application and efficacy of a particular mitigation technique for a particular problem. Bake-out is a promising technique for reducing exposures to VOCs in new office buildings. However, further effort in delineating its utility is necessary before it can be recommended.