The German Ad-hoc Working Group on Indoor Guidelines of the Indoor Air Hygiene Committee and of the Supreme State Health Authorities is issuing indoor air guide values to protect public health. For health evaluation of glycol ethers and glycol esters in air, the entire group of substances with data for 47 compounds was analysed in order to gain a unique assessment. For some glycol ethers reproductive and haematological effects are of central interest, whereas for others effects on liver and kidneys are crucial. Moreover, some glycol ethers were also shown to cause irritation of the respiratory tract. Fourteen compounds could be characterized either by relevant inhalation studies or by analogies drawn to strongly related substances. For these compounds individual guide values were derived, the respective guide value I ranging from 0.02-2 mg/m(3) (Tab. 2). The derivation of guide values considered the time exposure of the population as compared to working people or animal studies. The duration of the respective study, the interindividual variability--by a factor of 10--and the enhanced respiratory rate in children as compared to adults--by a factor of 2--were further taken into account. To allow for extrapolation from animal to human exposure differences in toxicodynamics were considered by a factor of usually 2.5. For compounds with insufficient data a default guide value II and I of 0.05 and 0.005 ppm, respectively, was recommended based on the statistical analysis of the available data of all glycol ethers. In order to achieve a total evaluation of all glycol ethers and glycol esters found in indoor air the proportional concentrations of each compound divided by the respective guide value were aggregated to give a total guide value. The total guide values are regarded to be complied with if their respective value falls below 1.

Concentrations of polybrominated diphenyl ethers (PBDEs), pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons were measured in 136 fish from 14 remote lakes in 8 western U.S. National Parks/Preserves between 2003 and 2005 and compared to human and wildlife contaminant health thresholds. A sensitive (median detection limit--18 pg/g wet weight), efficient (61% recovery at 8 ng/g), reproducible (4.1% relative standard deviation (RSD)), and accurate (7% deviation from standard reference material (SRM)) analytical method was developed and validated for these analyses. Concentrations of PCBs, hexachlorobenzene, hexachlorocyclohexanes, DDTs, and chlordanes in western U.S. fish were comparable to or lower than mountain fish recently collected from Europe, Canada, and Asia. Dieldrin and PBDE concentrations were higher than recent measurements in mountain fish and Pacific Ocean salmon. Concentrations of most contaminants in western U.S. fish were 1-6 orders of magnitude below calculated recreational fishing contaminant health thresholds. However, lake average contaminant concentrations in fish exceeded subsistence fishing cancer thresholds in 8 of 14 lakes and wildlife contaminant health thresholds for piscivorous birds in 1 of 14 lakes. These results indicate that atmospherically deposited organic contaminants can accumulate in high elevation fish, reaching concentrations relevant to human and wildlife health.