The German approach to regulate indoor air contaminants.

Indoor air quality (IAQ) and exposure to indoor chemicals are widely discussed in terms of personal discomfort and health risks. In contrast to ambient air and working environments, legally binding regulations are only partially established for indoor contaminants, and other available European guidelines are limited. To correct these deficits, the German Committee on Indoor Guide Values (AIR), formerly known as the Ad hoc Working Group (Ad hoc AG), performed health assessments of indoor air contaminants. The main tasks were to develop toxicologically based indoor air guide values, health-based guideline values, and reference values largely based on the 95th percentile of the concentrations found in a reference population. Here, we provide a comprehensive overview of the indoor air values set in Germany and discuss the basis of their derivation. This overview includes a description of legally binding standards, indoor air guide values for 38 substances or groups, and guidelines for TVOC (total volatile organic compounds), particulate matter, and carbon dioxide as well as risk-related guidelines for carcinogenic substances.

[Study on the potential impact of bromomethane on medicinal products following simulated container fumigation]. / Untersuchungen zur möglichen Beeinflussung von Arzneimitteln nach einer simulierten Containerentwesung mittels Brommethan.

To protect against exotic forest pest, solid wood packing has to be treated before shipping. According to the international standard ISPM 15 containers are usually fumigated with bromomethane. During this quarantine treatment a chemical reaction of bromomethane with the transported goods can not principally be excluded. This study takes a look at the impact of bromomethane on selected potential sensitive active pharmaceutical ingredients during simulated container fumigation. Following a 24-hour exposure to 67-80 g bromomethane per cubic meter, up to 0.02% bromide has been confirmed in phenacetine. The bromide concentrations in other active pharmaceutical ingredients were below 0.002%. New reaction products have not been identified at a detection limit of 0.01-0.04%. The bromide residue detected in one active pharmaceutical ingredient does not represent a relevant impairment of quality according to the European Pharmacopoeia, nor does it lead to a relevant excess exposure compared to both the acceptable daily intake of bromide and to the actual daily uptake of bromide from other exposure paths, dominantly from food consumption.

[Reference values for indoor air: dearomatized hydrocarbon solvents (C(9)-C(14))]. / Richtwerte für die Innenraumluft: Aromatenarme Kohlenwasserstoffgemische (C9-C14).

To protect public health the German Joint Working Group on Indoor Guidelines of the Federal Environmental Protection Agency and the States' Departments of Health is issuing indoor air guideline values based on a fixed procedure published in 1996. Regarding dearomatized hydrocarbon solvents/white spirits (DAWS--CAS-No. 64742-47-8, 64742-48-9, 64742-88-7, 64741- 65-7) no human data are available. From animal studies, neurotoxicity, developmental toxicity and reproductive toxicity were identified as critical endpoints. For risk evaluation the Hass et al. (2001) study was used as the pivotal study. Based on effects at 4680 mg DAWS/m(3) for the endpoint developmental toxicity, the lowest adverse effect level for chronic exposure is assessed as 400 mg DAWS/m(3). By applying an interspecies factor of 10, an intraspecies factor of 10 and an additional factor 2 referring to the special physiology of children (higher breath rate compared to adults) a so-called health hazard value of 2 mg DAWS/m(3) indoor air and a so-called health prevention value of 0.2 mg DAWS/m(3) are obtained.

PCDD/PCDF indoor exposure in day-care centers and PCDD/PCDF blood concentrations of female employees.

We determined blood concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in 41 female employees with previous exposure to pentachlorophenol-based wood preservatives from 10 day-care centers in the Hamburg, Germany, area. We compared the blood concentrations with estimated age-dependent reference values and analyzed the correlation between PCDD/PCDF indoor air exposure and blood concentrations. The analyses based on the PCDD congeners 1,2,3,4,7,8-, 1,2,3,6,7,8-, and 1,2,3,7,8,9-hexaCDD (hexaCDD), 1,2,3,4,6,7,8-heptaCDD (heptaCDD), octaCDD, and the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalents calculated according to the international NATO-CCMS model (I-TEQ). In comparison to the estimated reference values, the blood concentrations of hexaCDD and I-TEQ spread around the mean estimate. Data for octaCDD scattered in some cases distinctly above the upper confidence limit. Reference values for heptaCDD could not be estimated. The correlation between PCDD/PCDF indoor air exposure and PCDD/PCDF blood concentrations was examined by linear multiple regression analysis considering different exposure variables and taking confounders into account. Analyses were carried out with the total study group and with a restricted subgroup. Associations were shown between the PCDD/PCDF indoor air concentrations and blood concentrations for heptaCDD and for the I-TEQ, whereas hexaCDD showed no association. OctaCDD showed a negative association in the total study group and no association in the subgroup analysis. In summary, the analyses showed no clear association between PCDD/PCDF indoor air exposure in day-care centers and PCDD/PCDF blood levels of female employees previously exposed to wood preservatives. By contrast, the results consistently indicated a positive association between PCDD/PCDF blood concentrations and exposure to wood preservatives in private homes.

[Polychlorinated biphenyls indoors: attempt at an assessment]. / Polychlorierte Biphenyle in Innenräumen: Versuch einer Bilanz.

The use of products containing PCB in buildings resulted in indoor air contaminations. The search for appropriate measures is hampered by several different uncertainties in the regulatory toxicological process. These refer to problems in exposure assessment including measurement approaches, the toxicological evaluation of health risks including the derivation of a tolerable intake and the use of TCDD toxicity equivalency factors and finally the legal consequences of health risk evaluation. Since no consensus on these aspects has been achieved, the regulatory consequences vary considerably from one German state government to the other. FAO/WHO have not been able to arrive at a satisfactory supranational recommendation of a tolerable intake for PCB.

[Development of minimal requirements for site assessment and monitoring to estimate exposure in environmental medicine--the Hamburg approach]. / Entwicklung von Mindestanforderungen für Ortsbegehungen und Messungen zur Expositionsabschätzung in der Umweltmedizin--der Hamburger Ansatz.

As a further step towards quality management in environmental medicine the Hamburg Association of Panel Physicians and the Hamburg Department of Labour, Health and Welfare developed a consensus paper concerning the handling of indoor related problems. It focuses on the cooperation between environmental physicians and engineers. A critical point in the process of environmental health risk assessment is the selection of either human biomonitoring or environmental monitoring. Further well-known problems are quality of measures and process documentation. Accurate, reliable measures of individual exposure are an essential need for physicians who have to judge the potential impact of environmental contaminants on human health. The approach proposed in this paper was chosen to enable the patient and the physician to benefit from the special knowledge of environmental engineers on indoor related problems. The procedure and criteria might help to reduce misclassifications of diseases and the amount of measures with no medical relevance and to establish scientifically valid associations between health outcomes and exposures to environmental contaminants.

[Organic-chemical air pollutants indoors--aspects of environmental toxicologic evaluation]. / Organisch-chemische Luftverunreinigungen in Innenräumen--Aspekte der umwelttoxikologischen Beurteilung.

Indoor air pollution is characterized by a wide range of concentrations of many, mainly organic substances. To avoid adverse health effects it is necessary to develop indoor air quality standards. Standards should reflect the way and time of exposure and the fact that health risks might be possible especially to sensitive people. The toxicological basis for regulating indoor air quality is discussed. Special attention is given to organic substances with a cancerogenic and accumulating potential. An approach in setting standards of indoor air quality for frequent organic substances like toluene, xylene, styrene, dichloromethane, 1.1.1-trichloroethane, trichloroethene, tetrachloroethene, pentachlorophenol and PCB is presented, incorporating adequate protection margins. The results of this approach are compared with the WHO air quality guidelines and the German MIK values.