Wood-burning stoves and lower respiratory illnesses in Navajo children.

BACKGROUND: Acute lower respiratory illnesses (ALRI) have been associated with exposure to domestic smoke. To examine further this association, a case-control study was conducted among Navajo children seen at the Public Health Service Indian Hospital at Fort Defiance, AZ. METHODS: Cases, children hospitalized with an ALRI (n = 45), were ascertained from the inpatient logs during October, 1992, through March, 1993. Controls, children who had a health record at the same hospital and had never been hospitalized for ALRI, were matched 1:1 to cases on date of birth and gender. Home interviews of parents of subjects during March and April, 1993, elicited information on heating and cooking fuels and other household characteristics. Indoor air samples were collected for determination of time-weighted average concentrations of respirable particles (i.e. < 10 microns in diameter). RESULTS: Age of cases at the time of admission ranged from 1 to 24 months (median, 7 months); 60% of the cases were male. Matched pair analysis revealed an increased risk of ALRI for children living in households that cooked with any wood (odds ratio (OR), 5.0; 95% confidence interval (CI), 0.6 to 42.8), had indoor air concentrations of respirable particles > or = 65 micrograms/m3 (i.e. 90th percentile) (OR 7.0, 95% CI 0.9 to 56.9), and where the primary caretaker was other than the mother (OR 9, 95% CI 1.1 to 71.4). Individual adjustment for potential confounders resulted in minor change (i.e. < 20%) in these results. Indoor air concentration of respirable particles was positively correlated with cooking and heating with wood (P < 0.02) but not with other sources of combustion emissions. CONCLUSIONS: Cooking with wood-burning stoves was associated with higher indoor air concentrations of respirable particles and with an increased risk of ALRI in Navajo children.

Statewide assessment of lead poisoning and exposure risk among children receiving Medicaid services in Alaska.

OBJECTIVE: Lead poisoning is a well-recognized public health concern for children living in the United States. In 1992, Health Care Financing Administration (HCFA) regulations required lead poisoning risk assessment and blood lead testing for all Medicaid-enrolled children ages 6 months to 6 years. This study estimated the prevalence of blood lead levels (BLLs) >/=10 microg/dL (>/=0.48 micromol/L) and the performance of risk assessment questions among children receiving Medicaid services in Alaska. DESIGN: Measurement of venous BLLs in a statewide sample of children and risk assessment using a questionnaire modified from HCFA sample questions. SETTING: Eight urban areas and 25 rural villages throughout Alaska. PATIENTS: Nine hundred sixty-seven children enrolled in Medicaid, representing a 6% sample of 6-month- to 6-year-old Alaska children enrolled in Medicaid. OUTCOME MEASURE(S): Determination of BLL and responses to verbal-risk assessment questions. RESULTS: BLLs ranged from <1 microg/dL (<0.048 micromol/L) to 21 microg/dL (1.01 micromol/L) (median, 2.0 microg/dL or 0.096 micromol/L). The geometric mean BLLs for rural and urban children were 2.2 microg/dL (0.106 micromol/L) and 1.5 microg/dL (0.072 micromol/L), respectively. Six (0.6%) children had a BLL >/=10 microg/dL; only one child had a BLL >/=10 microg/dL (11 microg/dL or 0.53 micromol/L) on retesting. Children whose parents responded positively to at least one risk factor question were more likely to have a BLL >/=10 microg/dL (prevalence ratio = 3.1; 95% confidence interval = 0.4 to 26.6); the predictive value of a positive response was <1%. CONCLUSIONS: In this population, the prevalence of lead exposure was very low (0.6%); only one child tested (0.1%) maintained a BLL >/=10 microg/dL on confirmatory testing; no children were identified who needed individual medical or environmental management for lead exposure. Universal lead screening for Medicaid-enrolled children is not an effective use of public health resources in Alaska. Our findings identify an example of the importance in considering local and regional differences when formulating screening recommendations and regulations, and continually reevaluating the usefulness of federal regulations.