2013 Volume 24 Issue 2 Pages 123-128
In Japan, released amounts of certain chemical substances from sewage treatment facilities are reported and totaled while other chemicals are not reported or known. For this reason, a working group of the Ministry of the Environment has estimated the amounts for those non-reported substances. The total amounts for chemical inflow to sewage treatment facilities are estimated based on the “transfer to sewage system,” reported within PRTR system and the chemical amount calculated for domestic wastewater and road runoff. The total amount is then multiplied by the transfer coefficients to environmental media obtained mainly from measured data in order to estimate the amounts of chemical substances released into the environment through effluents, etc. Because the results contain certain estimates based on limited data, such as the concentration in road runoff and the biodegradability within sewage treatment facilities, it is still necessary to gather more data and improve the accuracy for these estimations.
