According to more than 200 scholarly publications, plastic pollution has been emerging as a major environmental concern in recent decades, and has been posing a relevant threat to ecosystems and global health. While the focus has primarily been on the physical, chemical and biological impacts of primary and secondary plastics, also for their ability to cross biological barriers within the human body, an additional hazard is represented by their association to heavy metals, used as additives. Metals are, in fact, added to plastics for their stabilizing actions. The examples of metal toxicity here reported are Antimony (Sb), Arsenic (As), Barium (Ba), Beryllium (Be), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Copper (Cu), Iron (Fe), Lead (Pb), Manganese (Mn), Nickel (Ni), Selenium (Se), Vanadium (V) and Zinc (Zn). This chapter explores the toxicity of metals associated with plastic pollution in the environment, illustrating their potential consequences for the global ecological system, with prevalent focus on human health. The interdisciplinary approach, which includes environmental science, chemistry and toxicology, aims to enhance the understanding of this complex issue and highlight the urgent need for efficient mitigation strategies.
Soil has various trace metals, which help to identify the demographical origin of the soil. The formation of soil undergoes changes due to several external factors. However, certain trace metals are not affected by these external factors. This chapter considers two approaches for the detection of these trace elements; first, it highlights the usefulness of the trace elements present in the soil whose presence in deficiency or excess affects the soil quality; second, the analysis of soil transferred from various surfaces, to detect the presence of these trace elements. This chapter involves various instrumental techniques used to study its elemental composition and morphological characteristics. Due to the heterogeneous nature of the soil, the information from this chapter can be used as a database to narrow down the area of search and objects under study. It also provides insights into understanding the presence of trace metals in soil, their effects, and their role in forensic soil science. The use of soil in the search for trace evidence, which gives background knowledge on the importance of comprehending soil from the topographical scale to the crime scene, has been overviewed. This aids law enforcement agencies in investigations.
It is predicted that electronic waste (e-waste) derived principally from discarded electronic equipment will reach 74 million metric tonnes by 2030. In addition, urbanization and industrialization have contributed to metal contamination in the environments. E-waste is often deposed of in low-income countries adversely affecting the health of the working population. The main sources of e-contamination are soil, dust, and food matrices. Drinking water can also be contaminated with heavy metals such as arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) causing a major health concern. Exposure to pollutants present in waste has a significant detrimental impact on human health; children in developing countries are often particularly susceptible. Sensitive monitoring procedures are needed to improve the rate of detection and monitoring of the possible adverse effects on the population exposed to significant quantities of e-waste.
Contamination of the environment by trace metals (TMs) has become a global health challenge. Some of these metals are found in some food substances in minute quantities as a normal part of nutrition. Excessive exposure of living organisms to these metals poses’ a great risk to the health of the living organisms. Once in the environment, these metals are not biodegradable and last for a long time. Their contamination of the environment leads to contamination of the ecosystem, which intricately depends on the environment. Normal physiological processes of the living organisms in these ecosystems are distorted following the dysregulation of their redox system. An imbalance in the ecosystem’s redox state led to damage to living organisms. There is an increase in mortality and morbidity, diversification is compromised, the genetic makeup of organisms is altered and over time the whole ecosystem becomes compromised. Several bioremediation techniques have been of valuable assistance in reverting this ugly trend. How well these remediation works could revert the damage and restore the ecosystems will be a measure of their survival, including all the dependent organisms and man.
As highly relevant environmental contaminants, metals and metalloids have been extensively evaluated for decades in biomonitoring programs, due to their potential toxicity at low levels and high persistence in many ecosystems. When considering chemical analysis, metal quantification has been carried out through conventional methods, based on the determination of their levels in internal organs, such as the liver and kidneys. Nevertheless, non-invasive methods constitute an alternative response regarding trace elements biomonitoring studies. Specifically, keratinized tissue from terrestrial mammals (such as hair, nails, or spines) presents a high accumulation rate, giving relevant information about heavy metal dynamics at internal levels and, most particularly, a chronic exposure. This critical review focuses on the use of non-invasive tissues, mainly hair and spines, as adequate tools on heavy metals assessment, specifically mercury (Hg) and lead (Pb), in biomonitoring studies performed in terrestrial wild mammals.
