Team:Oxford/P&P environmental impact
From 2014.igem.org
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<h1blue2>Humans</h1blue2> | <h1blue2>Humans</h1blue2> | ||
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- | The Reference Dose (an estimate of the maximum level of continuous exposure to the human population which is unlikely to pose any significant risk of detrimental effects (excluding the risk of cancer of the course of a lifetime)) for DCM is 0.06 milligrams per kilogram of body weight per day. Worryingly, DCM has been found in some urban air and at some hazardous waste sites at average concentrations of 11 ppb of air, and the average daily intake of methylene chloride from outdoor air in three U.S. cities may reach 309 micrograms per day, suggesting it is entirely possible that intake may exceeds the reference dose in individual cases. | + | The Reference Dose (an estimate of the maximum level of continuous exposure to the human population which is unlikely to pose any significant risk of detrimental effects (excluding the risk of cancer of the course of a lifetime)) for DCM is 0.06 milligrams per kilogram of body weight per day<font style="vertical-align: super; font-size: 70%;">1</font> . Worryingly, DCM has been found in some urban air and at some hazardous waste sites at average concentrations of 11 ppb of air, and the average daily intake of methylene chloride from outdoor air in three U.S. cities may reach 309 micrograms per day, suggesting it is entirely possible that intake may exceeds the reference dose in individual cases<font style="vertical-align: super; font-size: 70%;">2</font> . |
- | The most frequent and dangerous exposure to chlorinated solvents generally occur in workplaces where the chemical is present. Workers are at risk of breathing in chlorinated solvents or accidently coming into skin contact with chemicals. Previous studies have shown concentrations of up to 1,000 ppm of DCM in air (note that 1 part per million is 1,000 times more than 1 part per billion) have been detected in general work areas, and even higher concentrations of up to 1,400 ppm have been detected in samples in the breathing zone of some workers. Such exposure levels far exceed the current recommended federal limits; The National Institute for Occupational Safety and Health (NIOSH) estimated that 1 million workers may be exposed to dangerous levels of dichloromethane, and for chlorinated solvents generally the figure is much higher. | + | The most frequent and dangerous exposure to chlorinated solvents generally occur in workplaces where the chemical is present. Workers are at risk of breathing in chlorinated solvents or accidently coming into skin contact with chemicals. Previous studies have shown concentrations of up to 1,000 ppm of DCM in air (note that 1 part per million is 1,000 times more than 1 part per billion) have been detected in general work areas, and even higher concentrations of up to 1,400 ppm have been detected in samples in the breathing zone of some workers. Such exposure levels far exceed the current recommended federal limits; The National Institute for Occupational Safety and Health (NIOSH) estimated that 1 million workers may be exposed to dangerous levels of dichloromethane, and for chlorinated solvents generally the figure is much higher<font style="vertical-align: super; font-size: 70%;">3</font>. |
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- | DCM and other chlorinated solvents can have a devastating impact on human health. Case studies of DCM poisoning during paint stripping operations have shown that overexposure can be fatal to humans. Acute inhalation exposure can cause short term damage to the central nervous system including detriment to visual, auditory, and psychomotor functions, and irritation to the nose and throat. | + | DCM and other chlorinated solvents can have a devastating impact on human health. Case studies of DCM poisoning during paint stripping operations have shown that overexposure can be fatal to humans. Acute inhalation exposure can cause short term damage to the central nervous system including detriment to visual, auditory, and psychomotor functions, and irritation to the nose and throat. <br> |
- | The major effects of chronic inhalation of DCM are also effects on the nervous system, including headaches, nausea, memory loss, and possibly dizziness. There is currently a lack of research indicating whether there may be developmental or reproductive effects in humans, although animal studies have previously shown that if DCM passes through the placental barrier there is a high risk of skeletal variations and/or lower fetal body weight. DCM is also considered to be a probable human carcinogen. Although research in this area is incomplete, animal studies have shown a sharp increase in liver and lung cancer and in mammary gland tumors following exposure to DCM. The US Environmental Protection Agency has concluded that, by a weight of evidence evaluation, 'dichloromethane is [and should be treated as] carcinogenic by a mutagenic mode of action'. | + | The major effects of chronic inhalation of DCM are also effects on the nervous system, including headaches, nausea, memory loss, and possibly dizziness. There is currently a lack of research indicating whether there may be developmental or reproductive effects in humans, although animal studies have previously shown that if DCM passes through the placental barrier there is a high risk of skeletal variations and/or lower fetal body weight. DCM is also considered to be a probable human carcinogen. Although research in this area is incomplete, animal studies have shown a sharp increase in liver and lung cancer and in mammary gland tumors following exposure to DCM. The US Environmental Protection Agency has concluded that, by a weight of evidence evaluation, 'dichloromethane is [and should be treated as] carcinogenic by a mutagenic mode of action'<font style="vertical-align: super; font-size: 70%;">4</font>. |
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<h1blue2>Animals</h1blue2> | <h1blue2>Animals</h1blue2> | ||
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The No Observed Effect Concentration (NOEC) for the most sensitive species of plants was 46 μg/m. In some areas levels may exceed this, due to contamination of soil and groundwater. There is currently a worrying lack of understanding and research into the effects of chlorinated solvents on plant life. | The No Observed Effect Concentration (NOEC) for the most sensitive species of plants was 46 μg/m. In some areas levels may exceed this, due to contamination of soil and groundwater. There is currently a worrying lack of understanding and research into the effects of chlorinated solvents on plant life. | ||
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+ | <h1blue2>References</h1blue2> | ||
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+ | <font style="vertical-align: super; font-size: 70%;">1</font> Figures taken from: http://www.epa.gov/ttn/atw/hlthef/methylen.html (Environmental Protection Agency).<br> | ||
+ | <font style="vertical-align: super; font-size: 70%;">2</font> Figures taken from: See ibid.<br> | ||
+ | <font style="vertical-align: super; font-size: 70%;">3</font>National Institute for Occupational Safety and Health.<br> | ||
+ | <font style="vertical-align: super; font-size: 70%;">4</font> US Environmental Protection Agency (see specifically http://www.epa.gov/IRIS/subst/0070.htm). | ||
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Revision as of 00:01, 18 October 2014