From the best-fitting model, we derived inhibitory concentrations for antiandrogenicity and effect concentrations for cytotoxicity.
Due to the inherent error of light-scattering instruments, from the raw data, outliers outside of mean +/− three standard deviations were removed, prior to deriving mean concentrations for each sampling stop.
While some of the resulting (literature or experimentally derived) concentration values for many of these compounds might not be appropriate for routine clinical studies, they do provide a far more complete and quantitative picture of the plasma/serum metabolome than has previously been achieved.
The lyophilized samples were then resuspended in Dimethyl Sulfoxide (DMSO) and diluted further to derive the appropriate concentrations for testing.
LOD and LOQ both for the UV and the MS measurement step were calculated to address possible differences and derive applicable minimum concentrations for linearity testing.
Instead, where available, annual means from fixed site monitoring stations were used to derive past annual mean concentrations for pollutants with available historic data (NO2 and PM10 only).
Briefly, for both pollutants regression models were derived from annual mean concentrations for the year 2001 based on routine measurement data from the Dutch National Air Quality Monitoring Network (van Elzakker and Buijsman 2014).
From this robust fitting method, we derived effect concentrations (ECs) for androgenicity, with a 10% increase over the mean solvent mean as the minimum effect criterion, and ECs for cytotoxicity (if present) as 10% reduction of the maximal observed androgenic action.
Because there were BSM measurements for only six of the BSC plants, and those were very sparse, attempts to derive new summary mean BSM concentrations for the BSC plants and jobs by ANOVA were based on all NSF and BSC measurements, and the predicted concentrations by plant and job group plus a time trend were estimated.
Published studies involving formaldehyde were selected for quality and relevance for determining whether noncancer endpoints could be used to derive a reference concentration for formaldehyde.
