Introduction
Arsenic is an element that occurs naturally. It exists in both living things and minerals. Due to its toxicity and people’s inability to notice its effects, many people have used it for many years for homicidal purposes (ATSDR, 2014). This paper discusses the toxicological and epidemiological implications of arsenic through analyzing two studies and other sources that talk about arsenic.
Exposure Pathways for Arsenic
The main exposure pathways for arsenic are food, water and inhalation of contaminated air (Moeller, 2011). Children and pregnant women can also ingest arsenic through eating the soil. Research shows that food, especially seafood, carries the largest amount of arsenic (Roza, 2009).
Industrial exposure occurs when employees in industries inhale arsine gas (Büttner & Muller, 2011). People encounter arsine gas when it leaks from pipes during transportation. Sometimes, exposure occurs during the treatment of ores that contain arsenic with acids (Gordis, 2009).
Description of the Two Studies
The research in Human and Experimental Toxicology looks at the toxic elements of arsenic and its effects to the body. It also addresses various exposure pathways of arsenic and the best methods of diagnosis and treatment. It explains the process involved in the disintegration of pentavalent arsenic into trivalent arsenic. The product of this process is responsible for harming the body. In addition, it looks at the process through which arsenic causes neuro-toxicity.
The second study comes from The Journal of Exposure Science and Environmental Epidemiology. This study used the guidelines provided by the US Environmental Protection Agency, EPA, to determine the number of counties in the US whose wells contained excess arsenic. The researchers mostly used the EPA database in accessing information about the occurrence of arsenic in each county. Their analysis showed that the content of arsenic in drinking water in 33 counties exceeded the limit set by EPA (Frost, Muller, Petersen, Thomson & Tollestrup, 2003). Arsenic in drinking water is very dangerous. It can harm a very large population through food and other drinks that come from water (Wasserman et al., 2004)
Summary of the Two Studies
Aim
The aim of the study in Arsenic neuro-toxicity is to analyze the toxicity properties of arsenic and the way the toxins damage body organs. On the other hand, the second study aims at finding out the number of counties whose water contains excessive amounts of arsenic. The researchers wanted this information for epidemiological purposes.
Methods
Researchers who carried out the study on arsenic neuro-toxicity reviewed studies done by other scholars. They reviewed 85 sources that contained information on arsenic. The study on the concentration of arsenic in drinking water mainly used information from the EPA database.
Results
The results of the study on neuro-toxicity indicated that arsenic metabolizes when pentavalent arsenic disintegrates to form trivalent arsenic (Cooper, 2007). It then disrupts the manufacture and repair of Deoxyribonucleic Acid and the process of oxidative phosphorylation (Vahidnia, 2007).
Similarities Between the Toxicology and Epidemiology Methods
The similarity between the toxicology and epidemiology methods in the two studies is that they both used other researchers’ information. The research on toxicology used books and journals published by other scholars while that on epidemiology used the information that was published by EPA.
Differences Between Epidemiology and Toxicology Methods
The two studies were different in the sense that, the toxicology study reviewed different sources of information about arsenic while that on epidemiology interviewed people in addition to the information they obtained from the EPA database.
Conclusion
Arsenic is a toxic element that occurs in many forms. It can cause cancer and other fatal illnesses in case of direct contact with it. People should ensure that their food and drinking water are free from arsenic.
TEST: 2
- Question 1-A study finds that if rats are exposed to PCB and methylmercury together, the toxic effects of methylmercury are much greater than for rats exposed only to methylmercury. This means that in this study, PCB and methylmercury were found to be synergistic: TRUE
- Question 2-The hallmark of a toxic response is that adverse effects are immediate: FALSE
- Question 3-A control group in an environmental epidemiology study of whether dioxin exposure is associated with diabetes could be either those who were not exposed to dioxin or those who do not have diabetes: FALSE
- Question 4-Metabolism of a chemical always reduces its toxicity: FALSE
- Question 5-A study finds that maternal exposure to alcohol induces effects in offspring, such as facial abnormality and developmental delay. This study demonstrated that alcohol is a teratogen: TRUE
- Question 6-The data we may get from an acute study will generally include all but which of the following? Carcinogenesis
- Question 7-The study of toxicology is limited to understanding the effects of toxic agents on animals: FALSE
- Question 8- Humans are exposed to trace quantities of toxic chemicals in food: TRUE
- Question 9- One of the challenges of retrospective environmental epidemiology studies is determining just how much of the agent people were exposed to: TRUE
- Question 10- The Ames test is a short-term in-vivo test that uses rats to determine whether a chemical is carcinogenic: FALSE
References
ATSDR (2014). ATSDR – Toxicological Profile: Arsenic. Web.
Büttner, P., & Muller, R. (2011). Epidemiology (1st ed.). South Melbourne, Vic.: Oxford University Press.
Cooper, C. (2007). Arsenic (1st ed.). New York: Marshall Cavendish Benchmark.
Frost, F., Muller, T., Petersen, H., Thomson, B., & Tollestrup, K. (2003). Identifying US populations for the study of health effects related to drinking water arsenic. Journal of Exposure Science and Environmental Epidemiology, 13(3), 231–239.
Gordis, L. (2009). Epidemiology (1st ed.). Philadelphia: Elsevier/Saunders.
Moeller, D. (2011). Environmental health (4th ed.). Cambridge, Mass.: Harvard University Press.
Roza, G. (2009). Arsenic (1st ed.). New York, NY: Rosen Pub. Group.
Vahidnia, A., Van der Voet, G., & De Wolff, F. (2007). Arsenic neurotoxicity—a review. Human & Experimental Toxicology, 26(10), 823–832.
Wasserman, G., Liu, X., Parvez, F., Ahsan, H., Factor-Litvak, P., & van Geen, A. et al. (2004). Water arsenic exposure and children’s intellectual function in Araihazar, Bangladesh. Environmental Health Perspectives, 1329–1333.