Exposure to formaldehyde and asthma outcomes: A systematic review, meta-analysis, and economic assessment.

BACKGROUND: Every major federal regulation in the United States requires an economic analysis estimating its benefits and costs. Benefit-cost analyses related to regulations on formaldehyde exposure have not included asthma in part due to lack of clarity in the strength of the evidence. OBJECTIVES: 1) To conduct a systematic review of evidence regarding human exposure to formaldehyde and diagnosis, signs, symptoms, exacerbations, or other measures of asthma in humans; and 2) quantify the annual economic benefit for decreases in formaldehyde exposure. METHODS: We developed and registered a protocol in PROSPERO (Record ID #38766, CRD 42016038766). We conducted a comprehensive search of articles published up to April 1, 2020. We evaluated potential risk of bias for included studies, identified a subset of studies to combine in a meta-analysis, and rated the overall quality and strength of the evidence. We quantified economics benefit to children from a decrease in formaldehyde exposure using assumptions consistent with EPA's proposed formaldehyde rule. RESULTS: We screened 4,821 total references and identified 150 human studies that met inclusion criteria; of these, we focused on 90 studies reporting asthma status of all participants with quantified measures of formaldehyde directly relevant to our study question. Ten studies were combinable in a meta-analysis for childhood asthma diagnosis and five combinable for exacerbation of childhood asthma (wheezing and shortness of breath). Studies had low to probably-low risk of bias across most domains. A 10-µg/m3 increase in formaldehyde exposure was associated with increased childhood asthma diagnosis (OR = 1.20, 95% CI: [1.02, 1.41]). We also found a positive association with exacerbation of childhood asthma (OR = 1.08, 95% CI: [0.92, 1.28]). The overall quality and strength of the evidence was rated as "moderate" quality and "sufficient" for asthma diagnosis and asthma symptom exacerbation in both children and adults. We estimated that EPA's proposed rule on pressed wood products would result in 2,805 fewer asthma cases and total economic benefit of $210 million annually. CONCLUSION: We concluded there was "sufficient evidence of toxicity" for associations between exposure to formaldehyde and asthma diagnosis and asthma symptoms in both children and adults. Our research documented that when exposures are ubiquitous, excluding health outcomes from benefit-cost analysis can underestimate the true benefits to health from environmental regulations.

Baseline risk and marginal willingness to pay for health risk reduction.

Empirical results presented in this paper suggest that parents' marginal willingness to pay (MWTP) for a reduction in morbidity risk from heart disease is inversely related to baseline risk (i.e., the amount of risk initially faced) both for themselves and for their children. For instance, a 40% reduction from the mean of baseline risk results in an increase in MWTP by 70% or more. Thus, estimates of monetary benefits of public programs to reduce heart disease risk would be understated if the standard practice is followed of evaluating MWTP at initial risk levels and then multiplying this value by the number of cases avoided. Estimates are supported by: (1) unique quantitative information on perceptions of the risk of getting heart disease that allow baseline risk to be defined at an individual level and (2) improved econometric procedures to control for well-known difficulties associated with stated preference data.

Altruism, efficiency, and health in the family.

PURPOSE: The chapter investigates: (1) Do married parents efficiently allocate time to children's health care? (2) Are parents willing to sacrifice consumption for health improvements at an equal rate for all family members? (3) How does family structure affect health trade-offs parents make? (4) Are parental choices consistent with maximization of a single utility function? METHODOLOGY: A model is specified focusing on how parents allocate resources between consumption and goods that relieve acute illnesses for family members. Equivalent surplus functions measuring parental willingness to pay to relieve acute illnesses are estimated using data from a stated-preference survey. FINDINGS: Results provide limited support for the prediction that married parents allocate time to child health care according to comparative advantage. Valuations of avoided illness vary between family members and are inconsistent with the hypothesis that fathers' and mothers' choices reflect a common utility function. RESEARCH IMPLICATIONS: Prior research on children's health valuation has relied on a unitary framework that is rejected here. Valuation researchers have focused on allocation of resources between parents and children while ignoring allocation of resources among children, whereas results suggest significant heterogeneity in valuation of health of different types of children and of children in different types of households. SOCIAL IMPLICATIONS: Results may provide a justification on efficiency grounds for policies to provide special protection for children's health and suggest that benefit-cost analyses of policies affecting health should include separate estimates of the benefits of health improvements for children and adults.