Recently, cases have been reported of pigmented contact dermatitis from cotton flannel nightdresses caused by naphthol AS as an azoic coupling component. In this study, a method for the quantitative determination of naphthol AS in cotton flannel nightdresses was developed involving the use of anion exchange resin adsorption and gas chromatography. The chromatographic behavior of naphthol AS on an anion exchange resin was examined in order to eliminate many of the interfering compounds often present in sample extracts. The eluent and the anion type of the resin were discussed. The analysis showed that the content of naphthol AS was above 1000 ppm in most samples.
We selected design alternatives for a wastewater treatment facility for “Kamaboko” processing plant and compared them. They were chosen from among various activated sludge processes, such as conventional activated sludge process, batch-type activated sludge processes, and the modified activated sludge process. We first calculated each construction cost from the kinetic coefficients in our previous report [K. TAKAMIZAWA et al.: Seikatsu Eisei, 30, 15-18, (1986)], and then considered each economical cost on the basis of ordinary designing formula. Furthermore, we considered reliability and stability of each process. The authors came to the following conclusions. The modified activated sludge process, in which an aeration tank serves for both aeration tank and balancing tank is best from an economical standpoint. But, in consideration of stability of the effluent water quality, the batch-type activated sludge process in pararell appears best.
We examined the biodegradability of four polyglycerine-fatty acid esters (PGFE's), all non-ionic surfactants, and their influence on the water environment. The biodegradation rates of these esters by river water or activated sludge were equal to that of alkyl benzene sulfonate (LAS), when evaluated by TOC or BOD. Further, these rates were less than those of other chemicals such as polyoxyethylene lauryl acid ether (LPE), polyoxyethylene lauryl acid ester (PAE), aniline and glucose, respectively. TLm concentrations of these esters for killfish (Himedaka), Oryzias latipes, and their inhibitive concentrations for the growth of acetic acid-assimilating bacteria exceeded 1000mg/l in all cases. We concluded that these esters do not significantly hinder water self-purification nor have damaging effects on aquatic organisms.