Toxicologie environnementale et analytique

Sewage pollution poses significant risks to both public health and the environment. As urbanization and industrialization continue to expand, the volume of sewage produced increases, exacerbating the problem. Consequently, safeguarding against sewage pollution has become a critical concern for communities worldwide. This article explores the various assessments and actions necessary to mitigate sewage pollution effectively.

In our modern world, the issue of environmental contamination has become increasingly pressing. The presence of toxic substances in our air, water, soil and food poses significant risks to human health and the ecosystem as a whole. Environmental toxicology, the study of the adverse effects of environmental contaminants on living organisms, plays a crucial role in understanding and mitigating these risks. In this article, we will explore the challenges faced in navigating environmental contamination toxicology and discuss various strategies to address them.

Analytical toxicology plays a pivotal role in assessing and managing environmental hazards posed by various contaminants. With the increasing concern about the impact of pollutants on human health and the environment, there's a growing demand for robust analytical techniques capable of detecting, quantifying, and characterizing toxic substances. This article explores the methods and applications of analytical toxicology in environmental assessment, highlighting its significance in safeguarding ecosystems and public health.

This study examined the physicochemical properties of soil exposed to leachate from septic tanks within the International Secondary School of the Rivers State University, Rivers State, Nigeria. Soil samples were collected in quadruplicates from depths 0.0 m (surf), 0.5 m (sub), 1.0 m (deepsub) and 1.5 m(Msub) for each 0.5 m, 1.0 m,1.5 m and 2.0 m horizontal distances away from all eight sides of two septic tanks yielding a total of 128 samples. The samples were analyzed using standard physicochemical and AAS techniques, and the obtained experimental outcomes subjected to standard statistical treatment. The results showed that the means of the levels of pH, PO4, and Zn followed the order, surf>sub>deepsub>Msub. Other properties such as EC (Electrical Conductivity), TKN (Total Khejdhal Nitrogen), Ni and Cu also had highest levels of concentration or counts at the surface depth but did not follow this trend. Mn showed the highest occurrences at the Msub depth. The mean Ni level for the site was above the FMEenv and WHO maximum permissible levels respectively.

Environmental toxicology is a multidisciplinary field that examines the adverse effects of various chemical, physical, or biological agents on living organisms and ecosystems. As human activities continue to alter the natural environment, the need to understand and mitigate the impact of toxic substances has become increasingly crucial. From industrial pollutants to pesticides, the sources of environmental toxins are diverse and widespread, posing significant risks to human health and ecological stability.

Sri Lanka was among the 171 countries that signed the Paris Agreement in 2016 at the High- Level Signature Ceremony of the Paris Agreement held at the United Nations Headquarters in New York. Subsequently the country submitted the updated Nationally Determined Contribution (NDC) to the United Nations Framework Convention on Climate Change (UNFCC) in 2021. The Ministry of Environment, Sri Lanka prepared Carbon Net Zero 2050 Roadmap and Strategic Plan in 2023. The authors are responsible for the agriculture sector.

Agricultural lands contribute to the greenhouse effect primarily through the emission and consumption of Greenhouse Gases (GHGs) such as methane, nitrous oxide, and carbon dioxide. Synthetic fertilizers and organic materials after harvesting, and animal manure deposited during grazing are the most common sources that contribute to N₂O emission. Emission of CH₄ from agriculture is mainly from paddy fields and enteric fermentation of the livestock. Carbon dioxide is emitted from agricultural fields due to use of machinery, application of urea, dolomite and gypsum and tillage operations. However, when comparing the total GHG emissions from CH₄, N₂O and CO₂ from agricultural fields in Sri Lanka, it can be seen that the emission of CO₂ is negligible compared to other GHGs.

In the study three scenarios were adopted to predict GHG emission from agriculture up to 2050 – Baseline scenario, NDC 2030 scenario extended to 2050 and Improved mitigation scenario. The study included literature review, stakeholder discussions and analysis to determine strategies to minimize GHG emissions from the agriculture sector.

The study results showed that the NDC 2030 extended scenario and improved mitigation scenario can reduce GHG emissions by 30% and 60% respectively up to 2050 compared to the baseline situation. However, in achieving these targets the paper discusses issues and constraints and policy gaps, which would hinder the success of the efforts.