Hydrogen sulfide

Hydrogen Sulfide Pollution

Pollution in any form is a matter of concern as has been seen concerning some pollutants which have received a lot of attention from scientists, the government, and the press. Air pollution has important implications for the Earth’s environment and its inhabitants. Understanding brought about by studying these implications could help mitigate its effects and therefore improve the living conditions of people. This is especially true for people who are affected directly by pollution since it reduces life expectancy and quality. Through research, policies that are effective could be put in place to address the issue through efficient regulation and management of risks.

A key sulfurous gas that brings about pollution is Hydrogen Sulfide (H₂S). The gas occurs mostly in places where mining especially the mining of petroleum products- is taking place, in volcanic vents, in decaying waste, and around hot springs. In the United States alone approximately 125000 employees are exposed to Hydrogen Sulfide H2S (WHO 1991).

Hydrogen sulfide is a colorless, flammable gas and has a foul smell that is similar to the smell of rotten eggs of which it is responsible. The gas is toxic and affects several areas in the body but has greater effects on the nervous system. It is detected by humans at about 0.0047 parts per million (ppm). At about 150 to 250 ppm, an individual’s sense of the gas is reduced after inhaling the gas a few times which may reduce their awareness of its danger. At about 400 ppm, fluid increases in the lungs which may cause death while exposure to levels of about 500 ppm and above can cause immediate death due to the over-stimulation of the nervous system that may cause an increase in the breathing rate and eventual collapse of the individual.

If a person is exposed to low concentrations of the gas, the effects include; irritation of the eyes and throat, coughing, increased fluids in the lungs, and nausea. If the individual is exposed to low levels of gas long term, the individual becomes fatigued, irritable, loses appetite and memory, has headaches, and feels dizzy. Also, the gas may cause miscarriages on exposure for long periods of time. These health effects show the seriousness of pollution from the gas and therefore its levels, especially for vulnerable people such as those working in areas where it is produced, have to be monitored and regulated.

Hydrogen sulfide also has various environmental effects including harm to aquatic life which occurs when the gas ionizes. The gas is readily dissolved in water where it ionizes and affects organisms negatively. In the natural setting, the gas is produced by decaying matter and therefore effluents from industries and human waste management systems are sources of the gas and its pollution in natural water bodies. Hydrogen sulfide is mainly released into the environment in gaseous form where it is oxidized after about eighteen hours into other pollutants such as sulfur dioxide and sulfuric acid. However, it may also be released in the liquid form from industries.

Occupational exposure to hydrogen sulfide is especially important since individuals affected by this form have to spend long hours at their workplaces which increases the risks associated with exposure to the gas. Hydrogen sulfide causes great health damage as a result of long time exposure due to its cumulative and usually unacknowledged effects. Acute effects however are rarer since a high concentration of the gas is required for it to have adverse effects on people, but it may reach 70ppm on any gas detectors, and that have been witnessed around oil tank farms. Miners, sewerage, and both upstream and downstream crude workers handlers are the most vulnerable people to high concentrations while industrial workers and communities living in volcanically active areas are more vulnerable to small doses over a long period of time.

Occupational exposure is a serious issue with vulnerable groups. The gas can build up rapidly in confined spaces, which are prevalent in the above mentioned occupations, since the action of diffusion is less effective in them. Also, these spaces may be difficult to escape from and thus they compound the effect of the gas on people working in such areas. This is particularly evident for deep holes such as wells and man holes which limit the speed with which an individual could get out of the gas’ way. Since the gas could overwhelm an individual very fast, especially at sufficiently high proportions, confined spaces should be monitored by the use of instruments to ensure that they are safe before humans get into the areas. Multi gas detector, Job Safety Analysis (JSA), and hot work permit, are essential steps that could be taken before proceeding work in a suspected H₂S work environment.

Kuwait is well endowed with oil and it contains 9% of the world’s oil reserves and hydrogen sulfide is one of the major gases found in oil wells. Therefore, a lot of people in Kuwait are faced by the problem of air pollution in their jobs which should be a reason for increasing attention over the health risks associated with oil extraction. Performance of constant tests to establish the levels of gases in the region should be done to control of gas’ levels. Records about the presence of the gas and areas in which it is found should also be kept to ensure that special precautions are taken while drilling and working in areas where toxic gases are likely to be found.

The concern over hydrogen sulfide in Kuwait is extended by the fact that the gas has been found to be present in relatively shallow depths. In some suburbs of the Kuwait city, it has been reported to be in depths as low as 15 to 40 centimeters. Aquifers in the region have also been shown to have the gas in abundance which poses questions about the health of inhabitants and workers in the region (Mukhopadhyay, Al-Haddad, Al-Otaibi, & Al-Senafy 2007). The situation in Kuwait is compounded by the fact that the region has had vast mining interests and thus workers and inhabitants in general are faced by higher than normal levels of the gas.

Sewerage treatment plants like the one in Ardiyah have also been cause for concern in Kuwait over their mismanagement. Decomposing waste produces hydrogen sulfide and, if a sewerage system is not well managed, the gas’ level could rise into toxic amounts. Also, even if the levels are not high enough to cause acute health problems, the gas’ smell is irritating and thus it reduces the quality of life in the region. In Ardiyah, complaints by the public about maladies that could be associated with the gas illustrate its effects. In the plant itself, the gas level was at one point measured at about six parts per million (ppm). However, the level of the gas in the plant was at times measured at levels greater than that which is recommended with the highest level being 37 ppm. Outside the plant, the highest concentration was measured at about 0.53 ppm (Al-Shammiria 2004). The presence of workers in an area where the gas is in abundance could incrementally amount to serious health problems.

In an article by Al-Kazemi (2009), the levels of hydrogen sulfide in Kuwait are discussed with concern being raised over the amounts of waste being dumped in the sea and their implications for sea life. In the article, it is intimated that sewerage treatment is being seen as the way for reducing the environmental impact of human waste. With increased treatment of waste, more workers are needed to deal with the waste; therefore, there will be more negative health implications for the workers.

The environment is affected by pollution and it reduces the quality of life for humans and other organisms. An example environmental disaster is the Musher sewage plant which brought public objection and attention to the subject which is bound to cause increases in the workforce handling wastes. This is due to the fact that public views shape political decisions and priorities and therefore more occupations are likely to be created in dealing with waste (Al-Shammiria 2004).

The concern over the levels of hydrogen sulfide extends to construction projects such as the Kuwait underground metro that is undergoing construction. From a study done by the Kuwait Institute for Scientific Research, it was shown that Kuwait has a high amount of hydrogen sulfide in the ground which complicates the construction of the tunnel. It has, however, been proposed that some 60 kilometers of the metro should be underground and thus the construction workers will be faced by the increased danger of suffering grave health problems(Nadoum, Nadoum & Benjasem 2009). This shows that workers are vulnerable groups in reference to hydrogen sulfide poisoning and they should be protected through policies and regulations. These policies should address the need for cautionary and reparative measures should a problem arise that had not been anticipated.

Policies and regulations play a vital role in dealing with issues linked to pollution since they help protect waste management workers, construction workers and the public at large. These policies could also act as a guide in case a disaster comes about since they would allocate both resources and attention to the neediest areas (Tang & Al-Ajmi 2005). This is in view of the fact that, when disasters strike, people are often not prepared on the best way to react. Also, policies would help protect workers for any health problems they would experience through compensation.

The setting of standards should stem from environmental inputs observations and experimental evidence. Experiments are done in laboratories and they illustrate the dangers that could be faced by humans in certain air pollution levels. From this evidence, it would be possible to produce standards that are in keeping with the health needs of humans, organisms, and environmental demands. Prediction has been made easier with the invention of the computer and powerful computers have the capability of analyzing large amounts of data and extracting trends. Models that resemble real life situations are also useful in bringing up possible future trends (Tang & Al-Ajmi 2005). This is because current rates of pollution may not be harmful but continued pollution could incrementally bring about unacceptable levels of the gas.

In Kuwait, the effects of fossil fuel burning have been observed and documented. In1991, oil wells in Kuwait were set on fire in the war against Iraq. About 600 wells were set on fire with great effects being observed both in the environment and on human health. The smoke from the gaseous emissions was carried as far away as 1000 kilometers and the effect could even be seen from space. The fires burned for about 8 months releasing large amounts of harmful gases which included carbon monoxide, sulfur dioxide, carbon dioxide, nitrogen oxides and hydrogen sulfide. Also, the emissions contained other harmful gases and chemicals (Laurie 2004).Hydrogen sulfide and other chemicals such as carcinogenic substances had important implications for human health in the region during and after the fires (Laurie 2004).

The situation highlights the need for policies on the global scale that would prevent such acts since they cost both the country and the world as well. The Kuwait fires brings to the fore the health dangers that workers in the wells as well as in the army and relief agencies face from hydrogen sulfide and other harmful products produced at such time. Oil is an essential economic product in Kuwait and its sale should be accompanied by clear conditions on the portion of money obtained that should go towards reparations for the harmful effects produced by its being mined. As such, these funds could be better directed at controlling and addressing the negative environmental and human effects produced by the oil.

Through such a scheme, the workers as well as the general population would be protected and the strongest measures would be put in place to protect people against any eventuality. Economic gains that the country makes from oil sales would then go hand in hand with environmental and health gains thus leading to a balanced development for a healthier Kuwait. The need for management of the quality of air has been amplified by increase in industries and technologies that emit fumes into the atmosphere. Management involves the definition of terms, implementation of policies, control of air pollution, and constant evaluation of conditions. Through constant evaluation, measures which have been put in place can be changed to fit current conditions.

There are many instruments that can be used for air quality evaluation with the best being those that can record air quality in real time. These devices can measure hydrogen sulfide levels by the minute which is essential in that the gas is very poisonous (Tang & Al-Ajmi 2005). The devices could also be coupled with notifying instruments which would call to attention any violation on set standards. Actions over rapid changes in the gas’ level can therefore take place thus ensuring a safe environment for workers and communities that live in areas in which the gas is prevalent. From these measurements, the public and workers in risky areas would be provided with information that would help them deal with it. Since the public and some workers may not be educated on the amounts that are dangerous to them, schemes have been devised that help inform them of danger.

One of these schemes is the use of color coded messages that will show the level of hydrogen sulfide in the air at a given time. In Canada, the Index of Air Quality (IAQ) is used and it is an average of about one to twenty four hours. The index includes major pollutants and its scale is useful in that it is common and therefore comparison between areas is possible. Also, other pollutants may be included in the index which enhances its usefulness. With the adoption of methodologies such as these, air pollution would be decreased and response to its dangers would be fast (Tang & Al-Ajmi 2005). In places of work that have the risk of air pollution, publishing results would greatly reduce air pollution health effects on workers. Results on evaluations should be published according to the risk in the area. In a high risk area, results should be published at least hourly so that measures can be taken to avoid harmful effects.

The UK uses H₂S in many fields including research, metal treatment, and the production of dyes, chemicals, and pharmaceuticals. This large number of applications potentially exposes about 125,000 workers in the UK which shows the importance of policies for their protection. In oil and gas companies, about 3000 are potentially exposed to the gas (Costigan 2003).

In the   UK, occupational exposure limits (OELS) were updated to conform to recent studies which suggested that levels as low as 10 parts per million (ppm) were harmful to humans. The adverse physiological effect that these levels could have on people in occupations that places them in contact with the gas was considered. The limits had been set at 10 ppm in the short term and 15 ppm in the long term but this was put under revision after these new findings. The OELs have a legal basis in the Control of Substances Hazardous to Health Regulations (COSHH) which was enacted in 1988 (Costigan 2003). In the US, the American Industrial Hygiene Association has the same function.  The OEL is measured over a given period with the first being an 8 hour time weighted average (TWA) and the second being a short term exposure limit (STEL) of 15 minutes. The TWAs are useful in controlling the effects of slowly developing effects such as those produced by H2S in small doses. The STELs are used in controlling the immediate effects of a peak in exposure to a substance. If H2S is in large amounts, then the STELs are applicable while if it in small amounts, the TWA is applied. The maximum exposure limits (MLEs) are used to describe the levels that are deemed unacceptable since they would cause grievous health effects. Therefore, employers are legally expected to keep the level of harmful substances as low as possible and below the MEL level (Costigan 2003). These measures put the UK and USA ahead of Kuwait in designing methods through which occupational H₂S hazards are eliminated.

The effects of hydrogen sulfide will be addressed by actions such as the monitoring of its levels, ventilation of confined spaces and provision of fast escape routes. Also, activities by workers should be monitored to ensure that rescue operations take place as fast as possible. Procedures on access and dealing with eventualities should also be put in place in the working environment to ensure that rescue operations are fast and decisive. Safety features such as harnesses, respiratory devices, gas detectors, and fire extinguishers should be placed in high risk areas so that action is fast. Also, records on the activities of workers and areas with high amounts of gas should be kept to better identify areas that could prove dangerous. If these activities are coupled with the proper training and medical care, they would prove effective in taking care of workers as well as the general public (The Canadian Union of Public Employees (CUPE) 2009).

Through measures such as those taken by the UK which will address the problem of hydrogen sulfide emissions as well as other poisonous gases, Kuwait and other nations that take the same measures will have a healthy workforce which is essential for the generation of greater amounts of wealth since its output would be increased. Also, funds that could be directed to address health issues would be taken into other needy areas of the economy which would increase its growth. The environment, a subject that has captured attention in the recent past, would also be preserved for future generations. Also, by adopting control and preservation measures, the country would be acting responsibly not only for its own good but the world as a whole.

References

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