Legal obstacles to toxic chemical research

Legislative design impedes study of chemicals in the environment

Toxicity of environmentally important micropollutants on three trophic levels

Micropollution is a serious environmental problem caused by continuous entry of trace quantities of toxic chemical substances into the aquatic environment. In the present study, three trophic levels of the aquatic ecosystems were used to evaluate the acute toxicities of environmentally important micropollutants including heavy metals, pesticides and drugs. There is a scarcity of information on toxicity of the studied substances on marine water algae. Among studied micropollutants, the most toxic chemical to Daphnia magna and Danio rerio was found to be 1-Chloro-2,4 dinitrobenzene with EC50 of 0.002 and 4.2 mg/L, respectively. Although this compound was also toxic to marine algae, Phaeodactylum tricornutum, arsenic showed the highest toxicity to the algae with EC50 of 2.4 mg/L. As compared to other organisms, D. magna was found to have higher sensitivity to all of the tested micropollutants.

MATHEMATICAL MODELING OF THE PROCESS OF FUMIGATION OF LEGUMINOUS SEEDS IN A DRUM-TYPE INSTALLATION

Intensification of post-harvest processing of leguminous crops is an urgent task for the enterprises of the agro-industrial complex. The improvement of the known methods of ensuring reliable pro-tection of leguminous crops from the effects of pathogenic microflora, quarantine insect pests is of particular interest for research. The most common method of disinfection of products is con-sidered fumigation - the elimination of insect pests and pathogens with a gas or vaporous toxic chemical. The article discusses the process of fumigation of leguminous crops by an ionized flow of an aerodisperse mixture in a drum-type installation, and also presents the results of mathemati-cal modeling of this process. The mathematical description of the proposed model of the fumiga-tion process was carried out using the Mathcad application package. The analytical study of the obtained mathematical model allowed us to establish a number of dependencies and patterns char-acterizing the course of the process of electrostatic fumigation of leguminous crops in the mode of constant mixing.

Selected Essential and Toxic Chemical Elements in Hypothyroidism—A Literature Review (2001–2021)

Thyroid hormones are known for controlling metabolism of lipids, carbohydrates, proteins, minerals, and electrolytes and for regulating body temperature. Normal thyroid status depends on the chemical/elemental composition of body fluids and tissues, which changes depending on physiological state, lifestyle and environment. A deficiency or excess of certain essential chemical elements (selenium, zinc, copper, iron or fluorine) or exposure to toxic (cadmium or lead) or potentially toxic elements (manganese or chromium) interacts with thyroid hormone synthesis and may disturb thyroid homeostasis. In our review, accessible databases (Scopus, PubMed and Web of Science) were searched for articles from 2001–2021 on the influence of selected chemical elements on the development of hypothyroidism. Our review adopted some of the strengths of a systematic review. After non-eligible reports were rejected, 29 remaining articles were reviewed. The review found that disruption of the physiological levels of elements in the body adversely affects the functioning of cells and tissues, which can lead to the development of disease.

REMOVAL OF FORMALDEHYDE FROM WASTEWATER AND AIR: REVIWE

Formaldehyde is one of the most widely used and widespread aldehydes, and it has been classified as a toxic chemical and may be carcinogenic. Millions of tons of it are released annually into the environment, whether the environment is internal or external, as it is included in many industries in which it and its products are in direct contact with humans. It became necessary to remove formaldehyde, whether from air or water contaminated with it. The main purpose of preparing this paper is to review previous research in removing formaldehyde from waste water and the air by various methods and techniques, including chemical, biological and physical.

Surveying the Chemical Anthropocene

Faced with the non-optional acceptance of toxic chemical artifacts, the ubiquitous interweaving of chemicals in our social fabric oft en exists out of sight and out of mind. Yet, for many, toxic exposures signal life-changing or life-ending events, phantom threats that fail to appear as such until they become too late to mitigate. Assessments of toxicological risk consist of what Sheila Jasanoff calls “sociotechnical imaginaries,” arbitrations between calculated costs and benefits, known risks and scientifically wrought justifications of safety. Prevalent financial conflicts of interest and the socially determined hazards posed by chemical exposure suggest that chemical safety assessments and regulations are a form of postnormal science. Focusing on the histories of risk assessments of pesticides such as DDT, atrazine, PFAS, and glyphosate, this article critically reviews Michel Serres’s notion of “appropriation by contamination.”

Old town, Leh: Waste Management and Ecology

In this paper a research review is conducted considering the waste generated in the Old town area which lies in Leh, the capital city of Ladakh. If we trace back from 60’s era, Ladakh was a region where waste generation was negligible but as the time passes and improvement in infrastructure like road networks, army/military area development, increased influx of tourism, change in economy patter of Ladakhi families, lifestyle and way of living along with rapid growth of consumer goods, it experience changes for which the region was not prepared for. Due to this rapid urbanization mass production of waste started which started causing environmental misbalance. These waste are of various categories like, solid, toxic, chemical. Bio etc. Since waste was never considered as issue, less importance was given to it and thus when generation of waste increases, Leh lack in its management. Most of the waste was dumped in the area which was outside the habitable land mainly valley. Thus in the paper an attempt has been made to identify waste typology and how it can be reuse or renewed which can help in preservation of the existing ecology and environment. Also various measures and method adopted by the local authorities will be studied.