Mass Balance Method for Purity Assessment for Pesticide Analytical Standards

Imazamox, a widely used herbicide, is currently managed by the Pesticide MRLs and Positive List System of the Ministry of Food and Drug Safety, and the development of reliable standard materials for analysis is urgently required. To confirm the reliability of the mass balance method, we measured the purity of the imazamox reference material (RM) certified by an RM producer accredited with ISO Guide 34 and estimated measurement uncertainty. According to this method, the content of structurally similar organic impurities was measured using high-performance liquid chromatographic coupled with ultraviolet (HPLC-UV), and the moisture, volatile impurities, and non-volatile impurities were quantitatively analyzed using a thermogravimetric analyzer (TGA). Purity and measurement uncertainty were calculated based on analysis of the HPLC-UV and TGA results obtained, and the validity of these values was confirmed by comparing with the values provided in the RM certificate.

Quality Control Systems in UK : An On-site Assessments of Testing and Inspection Institutions

With reference to the quality standard, ISO/IEC 17025, we conducted on-site assessments of and comparisons between test and inspection institutions in Korea and the UK. The diversity of evaluation methods used ‘in the field’ within the UK is greater than the range in Korea. Nevertheless, when assessing on-site processes in both countries, it is clear that many aspects of the quality assessment, including the roles of the evaluation committee members, the preparation of documents for evaluation, the opening meeting, the evaluation process in the field, and the closing meeting, occur in a similar order in the UK as in Korea. However, one important difference between the on-site evaluations in Korea and the UK was noted; particularly, in the UK, the level of excellence achieved by the evaluated institution is highlighted during the closing meeting.

Evaluation of Health Risk from Concentrations of Heavy Metal in PM-10 and PM-2.5 particles at Sasang Industrial Complex of Busan, Korea

We investigated the distribution of hazardous heavy metals (As, Cr6+, Ni, Cd, Pb, and Mn) and estimated the health risk related to the heavy metals in fine dust (PM-10 and PM-2.5) of Sasang industrial complex, Busan, Korea. The concentration of fine dust in the industrial complex was 1.2 times higher than in a residential area, while harmful heavy metals showed a difference of at least 1.3 times (Cd) and up to 6.5 times (Ni). The concentration of fine dust and carcinogenic heavy metals in the industrial complex increased significantly compared to the residential area in spring (March to May) and winter (December to February) months. A risk assessment was performed using Monte-Carlo simulations containing a four-step procedure. During hazard identification, As, Cr6+ Ni, Cd, and Pb were categorized as human carcinogens and probable human carcinogens and evaluated for their levels of excess cancer risk. For concentrations of over 90% Cr6+ and As, the excess cancer risk was over 10-5 (1 person per 100,000). The non-cancer hazard index of As, Cr6+, Cd, and Mn was below the limit value of 1.

Analysis of the Toxic Effects of Bisphenol A on the Groups of Vertebrate Animals: a Comprehensive Review of Research 2015-2021

The toxic effects of Bisphenol A (BPA) have been studied in individual experimental animals under different conditions. However, without a systematic approach, it is difficult to compare and analyse the results because of differences in doses (concentration), dosing periods (exposure), research methods, and the effects of BPA. We systematically compared and analysed recent research (between 2015 and 2021) that examined the effects of BPA on individual experimental vertebrates (fishes, amphibians, birds, and mammals). We divided the experiments into two categories: experiments on fish and amphibians by indirect administration, and experiments on birds and mammals by direct administration. The deleterious effects of exposure to BPA were classified into two types: morphological and anatomical effects, and physiological and neurocognitive effects. Experimental animals that had less weight, were younger, and were farther away from humans in evolutionary relationships, showed toxic effects even if they were exposed to low concentrations of BPA in the short term. Long-term administration of a small amount of BPA and short-term administration of a large amount of BPA also showed severe toxic effects. When the parents absorbed BPA during puberty, just before fertilisation, or during pregnancy, toxic effects were transmitted from dosed parents to offspring. With increasing amounts of BPA production and waste, there is a growing possibility that animals in various ecosystems will be exposed to BPA. Therefore, it is necessary to identify the harmful effects of BPA on various animals and the conditions under which it affects them. We hope that the results reported here will contribute to the development of standardized study designs for BPA research, to ensure that results can be more readily compared.