introduction
Toxicology is the branch of science focusing on what we know about poisons, their actions, detecting them and treating illnesses they may cause through exposure. There are many thousands of substance which are regarded as toxins, both man-made and in nature. By-products of manufacture and other processes can generate different types of chemical waste, depending on what is manufactured and what chemical wastes are formed. Of course, many companies are trying to recycle chemical waste, logically being cost-effective, gentle on the environment and even profitable if the waste can be converted into another usable product.
In western society, poisons are not something that most people would think they come into contact with. With government regulations on food safety and the selling of prohited substances, or substances deemed unsafe for human use, we normally will not simply see these things on our local supermarket shelves. However, they are out there, usually where we don't expect them to be. Many toxins can find their way into our water supplies into our food chain, and in the air we breathe. Consider the air we breathe. Typical atmospheric air is around 21% oxygen. In a quiet country area, the air is not only normal oxygen content, but is lower in carbon monoxide and carbon dioxide. Trees filter the carbon dioxide for photosynthesis, as well as other particulate matter being "filtered" by the leaves. In a heavily industrialized area with a high degree of automobile traffic, the "localized" can have lower levels of oxygen, dangerous levels of carbon monoxide and dioxides, as well as other toxins. This can cause headaches, fatigue, and have other deleterious effects on the body, especially since inhaled carbon monoxide can permanently bond to haemoglobin in the red blood cell, rendering useless until it dies and is replaced.
Environental toxins also pose a significant potential threat. Seemingly harmless and even "wholesome" and healthy foods can cause significant illness and even death. Sea creatures can easily accidently store toxins in their body. While breathing through there gills, fish can filter any toxin suspended in the water they inhabit. Fish and other marine life that predate smaller life forms, will also accumulate any toxins that they haee acquired through predation. Imported shellfish have come with some particular dangers in the past. Shellfish such as mussels, clams, oysters, etc., have been taken from waters with algal blooms. These seasonal algal blooms produce some very potent toxins that mix with the water and hence, are filtered by the shellfish. Consumption of these shellfish have caused significant illness and even death. With regulations on fishing in prohited waters, etc., there is clearly an attempt to combat the problem. However, this is a problem that will alway be 100% regulated and of course, always present because of unforeseen algal blooms, migration of fish to other waters, etc. Plant products pose a noteable risk as well, considering like fish, plants extract their nutrients from their surroundings. Plants grown in contaminated soils accumulate toxins in their tissues, and if this is consumed by humans or other animals, poisoning will result.
detection
Detecting toxins is an interesting subject and the methods used vary. Environmental health in the area of toxicology is something that has grown considerably over the decades, in line with our increase in chemical knowledge. Detecting toxins in suspected places, foods, etc., involves sampling and testing. In this way the safety of water supplies, pools, natural bodies of water, land, food and anything else can be ascertained. Testing for poisons and other contaminants comes with its limitations. For example, if we were to test a parcel of land that has been suspected of having contaminated with waste via "dumping" we would have to take samples of that land. However, there is the statistical possibility that samples could be taken from the uncontaminated areas. This would yield a false negative result, or in other words, mistakenly give the land the "all clear" or a "clean bill of health". This can be disastrous, especially if that land were intended to be used for dwelling, farming, or tapped for a natural drinking water supply. The strategy employed to get a more accurate result is to take more random samples. The higher the sample number we obtain for testing, offers a probability that we will be able to detect the poison or contaminant. Many poisons and contaminants spread vertically (deep) into the soil, and not in a "widening" circular fashion, which sometimes makes detection difficult. Of course, we can attempt to be very thorough in our investigations and take samples every feet. Then the question arises regarding cost effectiveness. Does the money required in testing warrant the outcome (for example, if the land is going to be used for industry anyway). Additionally, laboratory error also must be taken into account. This is the logic behind increased sampling. As you can see, there is always room for error, both on the field and in the laboratory.
treatment
The most important part of toxicology is how poisons affect humans and their environments. If we have already have been exposed to a poison (eg., ingestion, inhalation, through the skin), the question of treatment arises. How do we treat the exposure and what future ramifications are there in regards to health? Some substances can be chelated in the body with specific remedies. Others cannot be removed, or can only be removed slowly. Asbestos, which was once a global problem (wherever asbestos insultaion was used), is within the last few decadees, shown mankind the severity of his own doing. Inhaled asbestos embeds itself in the tissues of the lung, causing concerning lung disease (fibrosis, cancer, etc.). Heavy metal and insecticide poisoning also come with particular difficulties in removal.
With the coalescing of expertise in many fields, we have accumulated a large database on poisons, their mechanism of action, and treatment from exposure. Unfortunately, many individuals have died along the way. At present and in the future, poisons will always be a potential threat. The best strategies we can adopt are rapid identification and better treatments for poisoning, increased education on toxicology for the general public, and continued research on dealing with both industrial and environmental poisons.
