[Dioxins and polychlorinated biphenyls in indoor areas]

Polychlorinated dibenzodioxins, dibenzofurans and polychlorinated biphenyls (PCB) today belong to the most significant and widespread contaminants. They are found in soil, sewage sludge, indoor and outdoor air, in food especially of animal origin as well as in breast milk. Based on available toxicological data the Federal Health Office and the Federal Office of the Environment suggested a tolerable daily intake (TDI) for PCB of 1-3 micrograms PCB/kg body weight in 1983 and for dioxins and furans of 1-10 pg TCDD toxic equivalents/kg body weight aiming at less than 1 pg equivalent in 1985. This allows for a risk assessment of indoor air pollution (for example in kindergartens, schools etc.). As a precaution the proportional daily intake of persistent environmental contaminants via indoor air should not exceed 10% of the TDI for longer periods. Step-by-step measures should be taken if there is any over stepping.