Xenobiotics are foreign chemical compounds present in any living organism. In other words, living organisms do not produce these chemical compounds or consume them deliberately in their diet. For instance, nearly all the drugs taken by humans are xenobiotics. The drugs come under this category, as we are unable to produce them physically, or do not consume these chemicals in ordinary situations. In addition, xenobiotics can also be described as chemicals that are present in our body in excessive amounts. Xenobiotics are absolutely synthetic chemicals and they came into existence only after humans began producing them artificially.
It is interesting to note that while one organism may find a chemical compound to be normal, the same chemical may be xenobiotic for another organism. A very common example of this phenomenon is the consequence endured by fish that subsist downstream from a sewage treatment unit's outlet. In fact, the water there or even that is treated may contain hormones made by humans and these hormones are basically chemical compounds, which are alien for the fish. Therefore, while the hormones are normal for humans, they are xenobiotic for fish.
There are other examples as well. For instance, various animals produce different types of toxic substances to protect them from predators. While these toxins are normal chemical compounds for animals producing them, they are xenobiotic for their predators. However, the predators may also produce the toxic substances to protect themselves. The instance of the coarse-skinned newt (an amphibian) and its killer, the garter snake, is quite interesting. The newt produces a chemical or xenobiotic called tetrodotoxin, which is generally an extremely poisonous substance for other animals. However, the garter snake has succeeded in developing a defense mechanism due to which it can resist this xenobiotic, continued to overcome the defenses of the newt and prey on it. Scientists presume that while the newt enhanced the production as well as the concentration of the toxic chemical over generations, the garter snake has also been progressively developing a more potent resistance to this xenobiotic, thereby neutralizing its effects.
When humans are exposed to such foreign chemical compounds, their body eliminates it by means of a process known as xenobiotic metabolism. During xenobiotic metabolism, the human body alters the chemical structure of this foreign body and breaks it down for its use or detoxifies itself. In fact, the body especially detoxifies itself when it is exposed to poisons. Often, the pathways as well as the reactions of these foreign chemical compounds may prove to be life-threatening, such as the severe side effects of some detrimental drugs and poisoning deaths.
As mentioned earlier, the human body gets rid of the foreign chemical compounds through a process known as xenobiotic metabolism, which involves rendering the xenobiotics inactive as well as excreting them. Most of this normally takes place in the liver. These deactivated xenobiotics are excreted from the body through several routes, including breath, sweat, urine and feces. Xenobiotic metabolism is undertaken by hepatic enzymes (enzymes produced in the liver), which activate them first by means of reduction, oxidation, hydration and/ or hydrolysis, and subsequently unite or fuse these deactivated secondary metabolites with sulphuric acid, glucuronic acid, or glutathione. Subsequently, the resultant product is excreted through bile or urine.
Various groups of hepatic enzymes, including hepatic microsomal cytochrome P450, are responsible for xenobiotic metabolism. In fact, the hepatic enzymes that are involved in this process are extremely vital for the pharmaceutical industry, as these are the same enzymes that are also responsible for breaking down different drugs in the liver.
In addition to defending them against xenobiotics and metabolizing these foreign chemicals inside their body, various organisms also possess the aptitude to evolve with a view to put up with xenobiotics. As said before, an ideal example is the evolution by the coarse-skinned newt and its killer, the garter snake. While the newt has been evolving over generations to develop a better defense mechanism against its predator and produce more toxic tetrodotoxin, the common garter snake too has been evolving to develop means to neutralize tetrodotoxin. In fact, this prey-predator pair has been engaged in an evolution race. While the prey has been producing more concentrated tetrodotoxin, the predator has been developing a superior resistance against this xenobiotic, eventually maintaining the ecological balance.
Since long, those involved with medical sciences have been taking keen interest in the metabolic channels used by the body for processing the xenobiotics or foreign chemical compounds. In fact, to a great extent, new drugs are proposed and developed after studying these metabolic pathways. This is even more important while developing chemotherapy drugs used for treating cancer. In addition, this is also vital for exploring the possible adverse influence of contaminants on an environment, to find out whether the foreign chemical is likely to be broken down in a particular environment or whether it will continue to exist in the environment and prove to be harmful.
Two types of chemical compounds, xenobiotics and xenoestrogens, are present in our environment as well as the food we consume. The action of these chemicals is similar to hormones. In fact, there is increasing evidence of the fact that coming in contact with these harmful chemicals may contribute to the risk of breast cancer, prostate cancer, testicular cancer, and reduction in production of sperms in males, in addition to various different grave health problems.
Majority of the xenobiotics have their origin in a particular petroleum source. Literally speaking, these chemicals are present in several thousand products, many of which are used by us daily. Some of the common products that enclose xenobiotics include foods, clothing, medicines, plastics, lotions, soaps, cleansers, herbicides, pesticides, microchips and several other things.
So what are xenoestrogens? Basically, they are a form of xenohormones that work in the same manner as the female sex hormone estrogen. Xenoestrogens can be natural as well as artificial chemical compounds. Artificial xenoestrogens are used extensively in the form of industrial compounds like BPA (Bisphenol A), PCBs (polychlorinated biphenyls) and phthalates. Although the chemical structure of these substances vary considerably from the estrogenic substances that are produced by the endocrine glands of any organism, their effect is akin to that of estrogen. On the other hand, naturally occurring xenoestrogens comprise phytoestrogens, which are also known as xenoestrogens derived from plants. Often, they are also known as "dietary estrogens," as we are mostly exposed to them when we consume phytoestrogenic plants.
Animal fats, especially dairy products and red meat, are the primary sources of xenoestrogens present in our food and we are exposed to them when we consume these foods. Any individual who consumes dairy products and meat obtained from conventional commercial sources is generally exposed to these harmful chemical compounds. In fact, cattle as well as chicken are fed with substances containing estrogen to ensure that they gain weight. Moreover, they also come in contact with xenobiotics when they consume foods that have been cultivated using fertilizers made from chemicals and pesticides.
What is actually dangerous is that both xenobiotics and xenoestrogens imitate the manner in which the hormones produced by our body naturally work. As these substances resemble the natural hormones very closely, the cells in our body also accept these molecules which are very much akin to those of the hormones. Nevertheless, these cells are not natural to our body or not natural hormones and, hence, they may or may not contaminate the healthy cells of our body. In fact, even if the hormone molecules miss a single atom the messages received by the cells will be incorrect, resulting in their malfunctioning.
In such circumstances, it is best to use organic products, as only this will help us to protect from the damages caused by these inescapable and detrimental chemicals. It is recommended that whenever possibly you should make use of natural products, which are not only safe for you, but also for the environment. At the same time, ensure that you take a diet that is rich in dietary fiber. Doing this will help your body to eliminate the toxic substances, instead of assimilating them. Most importantly, you should avoid red meat and dairy products and consume plenty of vegetables and fruits, if possible, organic.
You ought to know that whenever you cook your food in plastics, it increasing the seeping of these detrimental chemicals into the food you consume. Therefore, be careful. Findings of a recent study have revealed that cooking food wrapped in plastics in microwave ovens increases the level of DEHA, a carcinogen, by more than 10,000,000 times more than what is acceptable to the Food and Drug Administration (FDA). This study has also shown that this also augments the levels of xenoestrogens in our food.
In addition to consuming organically-grown foods, you should also try to take herbs as well as other different supplements, which assist in protecting and detoxifying the liver, whenever possible. It has been established that herbs like thistle and supplements like n-acetyl cysteine help the body to detoxify itself. At the same time, be careful not to use inferior quality supplements, which contain synthetic substances and unwanted fillers and incipients. In case you experience problems that are normally related to the use of too much estrogen, for instance, depressions, mood swings, prostate cancer, breast cancer, inexplicable weight gain, loss of libido and other problems, you need to think about using natural progesterone creams that will help to counter the effects of estrogen overload.
In fact, plenty of researches have been undertaken on this subject and they relate exposure to xenobiotics and xenoestrogens to health issues in humans as well as animals.