When chemical or microbial contaminants are assessed for potential effect or possible regulation in ambient and drinking waters, a critical first step is determining if the contaminants occur and if they are at concentrations that may cause human or ecological health concerns. To this end, source and treated drinking water samples from 29 drinking water treatment plants (DWTPs) were analyzed as part of a two-phase study to determine whether chemical and microbial constituents, many of which are considered contaminants of emerging concern, were detectable in the waters. Of the 84 chemicals monitored in the 9 Phase I DWTPs, 27 were detected at least once in the source water, and 21 were detected at least once in treated drinking water. In Phase II, which was a broader and more comprehensive assessment, 247 chemical and microbial analytes were measured in 25 DWTPs, with 148 detected at least once in the source water, and 121 detected at least once in the treated drinking water. The frequency of detection was often related to the analyte's contaminant class, as pharmaceuticals and anthropogenic waste indicators tended to be infrequently detected and more easily removed during treatment, while per and polyfluoroalkyl substances and inorganic constituents were both more frequently detected and, overall, more resistant to treatment. The data collected as part of this project will be used to help inform evaluation of unregulated contaminants in surface water, groundwater, and drinking water.

Objective: The objective of this study was to establish a national relative moldiness index for homes in the United States. Methods: As part of the Housing and Urban Development's American Healthy Homes Survey, dust samples were collected by vacuuming 2 m² in the bedrooms plus 2 m² in the living rooms from a nationally representative 1096 homes in the United States using the Mitest sampler. Five milligrams of sieved (300 μm pore, nylon mesh) dust was analyzed by mold-specific quantitative polymerase chain reaction for the 36 indicator species in 1096 samples. Results: On the basis of this standardized national sampling and analysis, an “Environmental Relative Moldiness Index” was created with values ranging from about −10 to 20 or above (lowest to highest). Conclusions: The Environmental Relative Moldiness Index scale may be useful for home mold-burden estimates in epidemiological studies.

Traditional environmental mould analysis is based on microscopic observations and counting of mould structures collected from the air on a sticky surface or culturing of moulds on growth media for identification and quantification. These approaches have significant limitations. A DNA-based method of mould analysis called mould specific quantitative PCR (MSQPCR) was created for more than 100 moulds. Based on a national sampling and analysis by MSQPCR of dust in US homes, a scale for comparing the mould burden in homes was created called the Environmental Relative Mouldiness Index (ERMI).