The hockey stick regression method is a convenient method to estimate safe doses, which is a kind of regression method using segmented lines. The method seems intuitively to be useful, but needs the assumption of the existence of the positive threshold value. The validity of the assumption is considered to be difficult to be shown. The alternative methods which are not based on the assumption, ...

In the ISA, EPA indicates that many of the overall conclusions remain generally the same as the last National Ambient Air Quality Standard (NAAQS) review which was completed in 2008. However, contrary to the EPA’s statement, the ISA includes conclusions regarding a wide-range of health effects including stronger causal associations for both short-term and long-term exposures to ozone and newer ...

Solar radiation produces harmful compounds such as atmospheric oxidants and pharmaceutical intermediates through photochemical reactions. To clarify the variables related to formation of oxidants, hourly data air pollutants climatic conditions in Tokyo region Japan from late May early June 2020 were analyzed. Air pollutants, NO, NO2, CO, SO2, NMHCs CH4, significantly lower than those 2019. It s...

VOCs comprise both methane (CH 4) and non-methane volatile organic compounds (NMVOCs). NMVOCs are defined as " all those artificial organic compounds different from methane which can produce photochemical oxidants by reaction with nitrogen oxides in the presence of sunlight " .

Atmospheric photochemical oxidants nitric acid, ozone, and hydrogen peroxide were monitored in ambient air at Mt Mitchell State Park, North Carolina. Ozone measurements made from May to September during 1986-1990 are reported for two high-elevation sites (Site I on Mt Gibbs, approximately 2006 m; and Site 2 on Commissary Ridge, approximately 1760 m). These measurements are also compared to thos...

Indoor, outdoor pollutants and climatic conditions in the growing environment can develop childhood asthma atopic dermatitis. Therefore, it is important to identify environmental burden of community on risk To clarify relationship between regional prevalence rate dermatitis among first grade elementary school students preschool indoor such as smoking rate, photochemical oxidants concentration, ...