Q Essay explains Exposure to Toxics deals with materials that are biodegradable in the contaminated ground water Home, - Exposure to Toxics Exposure to Toxics Contaminated ground water may be remediated through various methods. The first method is bioventing which involves the introduction of microorganism in the underground water to help in the biodegradation of the underground water system. The advantage of this approach is that it is a natural process without further contaminations. However, the demerit of this biological process is that it only deals with materials that are biodegradable in the contaminated ground water. The surfactant enhanced recovery which subjects the surfactant into the contaminated water to ensure that thick aqueous liquids are removed (Khan, Husain, & Hejazi, 2004). The advantage of this process is that the surfactants do not get absorbed in the treated water and there is another additional process taken when the water is taken above the ground. The disadvantage is that the surfactants are not readily degradable. The other method includes the pump and treats methods in which water is taken to the surface for further treatment. The advantage is that the method is easy to undertake. The disadvantage is the pumping activities may not be possible in areas of low permeability. The fourth method that can be applied is the soil vapor extraction in which the extraction wells are used in removing the volatile contaminants from the soil and water (Khan, Husain, & Hejazi, 2004). The method is beneficial since it helps in dealing with the highly volatile materials. However, the method is less efficient in low permeable areas. The ex-situ and the in situ types of soil treatment have significant differences and similarities. The in situ approach involves the treatment of the soil components in the direct sites where they were accessed. On the other side, the ex-situ include the treatment of the contaminated water away from the areas where they were accessed. The other aspect of in situ approach is that it is cost effective and ensures that no chemicals and dust are distributed to the outside surroundings (Khan, Husain, & Hejazi, 2004). The common processes that are used in the in situ approach include the aerobic processes which enhance the infliction of air into the soil. Some of the most common techniques that apply these methods include bioventing and hydrogen peroxide injection. On the other side, the ex situ treatment approach is known for the ability to treat most of the soil and water contaminants once they have been extracted. Slurry phase and solid phase bioremediation are some of the two methods that may be used in performing the ex situ treatment approaches. The routes of human exposure to hazard materials may be defined as the possible areas of entry of the contaminants into the human body. One of the routes of entry includes the aspects of inhalation. Through the nose, an individual can inhale gasses, mists, and vapor that are considered as toxins from the contaminated water or soil. The inhaled gasses or mists may get into the respiratory track hence causing damage. The skin absorption is another means by which the human beings may get exposed to the hazard materials. The absorption of chemicals into the skin is some of the ways in which the skin may expose the human beings to various damages. Ingestion is another option through which people may get affected by the contaminated materials (Khan, Husain, & Hejazi, 2004). However, ingestion is least likely to increase the toxic levels. For instance, the non-soluble elements are excreted from the body. They may only affect the digestive tract if they have a corrosive nature. Acute exposure is the element in which an individual has a one time or multiple exposures that do not last a long time. The ideal time range for such exposures is 24 hours. For example, inhaling toxic gas from a burning dumping site is an acute exposure. However, chronic exposure may be described as getting in touch with toxic chemicals in a continuous manner for a long period such as four months. Continuous drinking of water from a contaminated source is an example of chronic exposure. The subchronic exposure refers to the different and constant exposures that may be considered to last about 10% of a specimen lifetime. For example, exposure to poisonous gasses for more than 30 days is an example of subchronic exposure.