Radiation and Heavy Metal Pollution Lecture 9 PDF

Radiation and heavy metal pollution Lecture 9_ADI Radioactive Pollution Radioactive Pollution or radiation pollution is a type of Physical type of environmental pollution. Radioactive pollution can be defined as the emission of high energy particles or radioactive subs...

Radiation and heavy metal pollution Lecture 9_ADI Radioactive Pollution Radioactive Pollution or radiation pollution is a type of Physical type of environmental pollution. Radioactive pollution can be defined as the emission of high energy particles or radioactive substance into air, water or land due to human activities in the form of radioactive waste.  Radiations are classified into two types, they are: ✓ Non-ionizing radiations ✓ Ionizing radiations  Based on the frequency with which it occurs, radioactive pollution can be Types of Continuous Radioactive Pollution Occasional Accidental.  1. Natural Sources Ex: Cosmic rays; Terrestrial Radiation from the earth such as Radium -224,Uranium 235, Uranium 238,Thorium 232. Radon 222. SOURCES 2. Man made Radiation Ex: Nuclear Accidents From Nuclear Energy Generation Plants; Fukushima Daiichi nuclear disaster (2011), Chernobyl disaster (1986), and Three Mile Island accident (1979)  Type of radiation Effect on body Alpha particles An alpha particle cannot enter the skin but if their sources are present inside the body then they can damage lungs and bones. Beta particles Beta particles can go inside the skin but cannot damage tissues. They have the ability to damage to eyes and skin. X-rays X-rays have ability to pass through tissues and travel far. They cannot travel through bones. They can damage cells. Gamma radiation They have an ability to easily enter the body and pass through it. Cell structure can get damage because of them.  Proper Method of Banning of Disposing of Proper Labelling Nuclear Tests Radioactive Waste Solutions to Radioactive Alternative Energy Sources Proper Storage Reusing Pollution Precautions at the Personal Level Disposal of Radioactive Waste  Nuclear waste is segregated into following classifications. 1.Low level waste which is not dangerous but sometimes requires shielding during NUCLEAR handling. CLASSIFICATIONS 2.Intermediate waste typically is chemical sludge and other products from reactors. 3.High level waste consists of fissionable elements from reactor core. 4.Transuranic waste is any waste with transuranic alpha emitting radionuclides whose half-life is longer than 20 years.  Waste Volume 7% 3% 90% Low Level Waste Intermediate Level Waste High Level Waste  Waste generation occurs during the operational period. It can be in the form of solid, liquid or gaseous waste. Radioactive Pretreatment is the initial step that Waste occurs just after generation. It consists of collection, segregation, chemical adjustment and decontamination. Management Treatment involves changing the characteristics of the waste. Basic treatment concepts are volume reduction, radionuclide removal and change of composition. Disposal of Low Level Waste Incineration is common with low-level waste, as this material usually consists of clothing or other common items that have simply been contaminated.  Near Surface Disposal: Disposal in a facility consisting of engineered channels or vaults constructed on the ground surface or up to few tens of meters below ground level. These type of wastes loses most or all of its radioactivity within 300 years. It includes contaminated equipment from the operation of nuclear power plant like clothing, rags, tools and equipment. Very short-lived low-level radioactive waste such as that from hospitals, universities and industry generally contains only small amounts of radioactive materials with short half-lives. This means that radioactivity decays away in hours or days. DISPOSAL OF INTERMEDIATE LEVEL WASTE Depending on its characteristics, intermediate level radioactive wastes can be disposed in facilities of different types. Disposal could be by emplacement in a facility constructed in caves, vaults or silos at least few hundred meters below the ground level. Intermediate level radioactive wastes require long-term management. These are much bulkier materials and are first sealed in steel drums and are encased in concrete trenches.  DISPOSAL OF HIGH LEVEL WASTE Geological disposal: disposal in a facility constructed in tunnels, vaults or silos in a particular geological formation at least a few hundred meters below ground level. Such a facility could be designed to accept high level radioactive waste (HLW), including spent fuel if it is to be treated as waste. ✓ First used in 1999 in the US. Deep Boreholes: Deep borehole disposal is the concept of disposing high-level radioactive waste from nuclear reactors in extremely deep boreholes instead of in more traditional deep geological repositories that are excavated like mines. ✓ Similar concept to geological repositories. ✓ Kilometers deep rather then hundreds of meters. ✓ Provide further insulation from ground water. Vitrification It is a technique for the transformation of a substance into a glass (non-crystalline amorphous solid). Borosilicate glass is mainly used as medium for dealing with High Level Waste. The solidified waste is stored in stainless steel containers. Principle aims are: 1. Minimise the volume of waste. 2. Reduce potential hazard by conditioning it into solid form. OTHER IDEAS FOR DISPOSAL  Heavy Metal Poisoning  Heavy metals are naturally occurring elements th at have a high atomic weight and a density at least 5 times greater than t hat of water (specific gravity of more than 5gm/cm 3). They have a relatively high density and are toxic What are Heavy or poisonous at low concentrations. Heavy metal pollution can originate from natural Metals? and anthropogenic sources Heavy metal poisoning is caused by the accumulation of certain metals in the body due to exposure through food, water, industrial chemicals, or other sources.  Heavy metals are dangerous because they tend Why Heavy Metals to bio-accumulate. Bio-accumulation means an increase in the concentration of a chemical in a biological organism over time, compared to the are Poisonous? chemical's concentration in the environment. Compounds accumulate in living things any time they are taken up and stored faster than they are broken down (metabolized) or excreted. How are people exposed to Heavy Metals? Heavy metal contamination may occur due to factors including irrigation with contaminated water, the addition of fertilizers and metal based pesticides, industrial emissions, transportation, harvesting process, storage and/or sale People may be exposed to small amounts of heavy metals through food, water, air, and commercial products. People can also be exposed in their workplace, as several industries use or produce these metals. If these metals accumulate in the body in concentrations sufficient to cause poisoning, then serious damage may occur.  Ba As Cd Al Cs U List of Heavy Metals Cu Th Hg Sn Pt Ni Chronic Effect of Heavy Metals: CNS/PNS: predominate Heme: anemias, cytopenias Renal: CRI/CRF CA: Various Skin: Rashes, colored lines on nails/gums  GI: Nausea/vomiting/diarrhea-most metal ingestions Renal: Proteinuria, aminoaciduria, ATN Acute Effect of CV: Response to volume loss, dysrhythmia, Heavy Metals: congestive CM CNS: dMS; periph neuropathies in hours to days Hair/skin/nail changes: lag days –wks behind acute exposure  Acute Effect Chronic Effect Occurs form accidental ingestion of Multisystem disease : malignancy pesticides and less commonly suicidal attempts Respiratory Effect: Respiratory failure Anaemia , leukopenia , Acute and and pulmonary edema GI Effect: nausea, vomiting, colicky Thrombocytopenia Cutaneous changes: initial persistent chronic effect of abdominal pain, and profuse watery erythematous flush slowly, over time, diarrhoea. leads to melanosis, hyperkeratosis, and desquamation Arsenic (As) Hematological abnormalities: haemaglobinuria, intravascular coagulation, bone marrow depression, non-specific symptoms : abdominal pain, diarrhoea, and sore throat. severe pancytopenia, Renal Effect: Renal failure Interference of Anemiawith folate metabolism and DNA synthesis may result in megaloblastic changes.  Acute Effect Chronic Effect Primary target : The respiratory tract Inflammatory changes in the respiratory tract due to chromium (III) salts Occupational asthma in sensitized Nasal septum ulceration and perforation, Acute and individuals respiratory irritation, lung cancer and possible renal effects by chronic inhalation of high level of chromium (VI) chronic effect of Hepatic damage Chronic dermal exposure can result in Chromium (Cr) deeply penetrating skin ulcers Cardiovascular, gastrointestinal damage Chromium (VI) compounds have due to ingestion of large amount of mutagenic potential Chromium Potentially death Chromium (VI) compounds are carcinogenic to humans and Potassium dichromate may be toxic to the reproductive system and the developing fetus.  Acute Effect Chronic Effect This is rare. Many reported cases of MILD TOXICITY (BL 40 -60 acute poisoning may be actually be mcg/100m1) : exacerbations of chronic lead poisoning Fatigue ,Irritability ,Abdominal when significant quantities of lead are discomfort suddenly released into the bloodstream Acute and from bone. GI effect: constipation or MODERATE TOXICITY (BL 60-100 chronic effect of diarrhea(black mcg/100m1): Arthralgia ,Headache, stool) , vomiting Tremor ,Muscular exhaustibility, Diffuse abdominal pain ,Anorexia, Lead (Pb) metallic taste, vomiting , Weight loss ,Hypertension , Constipation CNS effect: hyperactivity or lethargy SEVERE TOXICITY (BL more than ataxia , behavioral changes ,convulsions 100mcgiml) :Lead palsy: wrist or foot drop ,A bluish black lead line on gums, Lead colic : severe - abdominal cramps, Lead encephalopathy. Other effect: metallic taste ,abdominal pain  Acute Effect Chronic Effect Local Effects - Classic symptoms: tremor, Oral ingestion (chiefly gingivitis, erythrism inorganic salts) (Greek erethismos = irritate) Acute and gastrointestinal: pain, vomiting, diarrhea, hemorrhage Inhalation: chronic effect of Pneumonitis, metal fume fever (Hg0) Mercury (Hg) Systemic Effects - Shock Renal & CNS damage Kidney (inorganic salts) CNS: lethargy, (shock related effects) Metallic taste, sore gums, salivation Minamata disease - neurological syndrome caused by severe mercury poisoning  Heavy Metal Poisoning According to Bangladesh Aspect Arsenic contamination in Bangladesh Arsenic contamination of ground water is a major public health concern in Bangladesh Chronic toxicity of arsenic in humans from arsenic contaminated drinking water occurs in 61 of 64 districts in Bangladesh. The maximum permissible level of arsenic in drinking water is 10 µg/L (WHO, 2008) and in Bangladesh, it has been adjusted to 50µg/L by the local authorities A survey showed that arsenic related diseases resulted in 9136 deaths per year and 174 disabilities In Bangladesh, raw rice contains higher concentration of arsenic compared to raw vegetables Lead contamination in Bangladesh A study with fish and water of Turag river found high lead in water samples (0.1169±0.041 ppm) (Maximum allowable concentration is 0.05 ppm) and Lia fish (3.8656 ± 1.041 mg/kg) (FAO standards-0.10 mg/kg Another study with samples from central market of Rajshahi, Bangladesh found high Pb in fish "Major carp" A study by BRRI showed that one sample of rice collected from industrial field of Narayanganj district have a very high amount of lead (0.242ppm) Another study with water and plants samples from area around Tejgaon industrial area found the level of Pb to be much higher than the permissible levels of WHO and USPH standard. A study in Jessore district found high lead level in vegetables like ghotkol, elephant foot, bottle ground leaf and stem amaranth (1.689, 0.967, 0.987 and 0.831 µg/g respectively). Mercury contamination in Bangladesh It is estimated that the release of mercury from the 33 cement factories of Bangladesh is 0.56265 million tonnes. A total of 1.44 million tonnes mercury is released per year from paper and pulps mills in Bangladesh. Based on the same ESDO survey, 1.09 -6.22 million tonnes mercury vapour is released from mercury amalgam fillings per year from dental sector in Bangladesh. It is estimated that potential mercury emissions from the energy sector is 3058.158kg. Besides, mercury release from CFL light bulb is 0.118 million tonnes. Also Mercury release from jewellery sector was estimated to be 4.1 million tonnes. Bangladesh has no specific guidelines regarding the management of mercury disposal or how to safely manage the use of products or equipments that contains mercury or mercury compounds. Chromium contamination in Bangladesh In Bangladesh, among the routes of chromium eco-toxicity, feeds and fertilizer production from tanned skin cut wastes is the most direct one leading to food chain contamination A study by Bangladesh livestock research institute (BLRI) found high chromium (0.53 to 0.96 ppm) in all milk samples of both brand and local vendors compared to the IAEA values (0.22 to 0.29ppm) A study with "Stinging Catfish" of Turag river of Dhaka found high chromium (1.46mg/Kg) in fish body A study with vegetable samples grown at Gazipur district showed that the concentration of chromium (21.9-22.9µg/g) was higher than the maximum allowable level (WHO-1.3µg/g)  ❑In the Buriganga river fish, water and sediment are being contaminated by industrial wastes, municipal wastes and pesticides. The heavy metal concentrations (Pb, Cr, Mn, Co, Ni, Cu, Zn, As, and Cd) in water and sediment were very high and in most cases, exceeded permissible limits recommended by the Bangladesh government and other international organizations. Heavy Metal ❑ The Turag River near Dhaka city is being severely polluted by industrial waste waters and urban sewage from the Tongi municipal and industrial area. Cr, Cu, Zn belongs to the category Pollution of of moderately to highly polluted. The amount of Mn, Fe and Cd exceeded the allowable limit set by WHO River Water ❑There are many industries close to the Karnafully river bank witho ut any waste management system. Heavy metals were found above the permissible limit in pore water of salt marsh along the Karnafully river coast. Cd exceeded the recommended values and deliberates little sign of presence of metal pollution in the Karnafully River. There is a higher concentration of Pb in Chapila fish.. Heavy Metal Pollution of River Water ❑ The Meghna river is also polluted with heavy metals because of rapid urbanization and industrialization. The water, sediment and fishes of the Meghna river contaminated with heavy metals. Pb and Zn concentrations were found above the permissible limit in 15 fishes. The concentrations of Cd, Cr, Mn and Zn in the Meghna river water are lower but Fe is higher than standard guidelines ❑ Due to the geographical location of the Shitalakshyaa river, various metals were found in excess amount. The amount of Al, Cd and Mn exceeded the recommended value set by WHO. The concentrations of Pb, Fe, Cu and Zn were found below the permissible limit. The concentrations of heavy metals (Cd, Cr, Ni, Pb and Zn) are extremely higher than Bangladesh standard for drinking water. Heavy Metal Pollution City Area Coastal Area ✓ Ship breaking area in Chittagong is highly In Dhaka, Kushtia, Gazipur, Savar, affected by heavy metal. The sediment Mymensingh, Bogra and Chittagong , heavy samples were moderately to heavily metal accumulation in the soils is a concern polluted with Pb, Cu, Zn and Cr but the of matter because of its potential health risks concentrations in water were found below and detrimental effects on soil ecosystems. the permissible limit. ✓ Bay of Bengal coast’s sediment was highly polluted with heavy metals that originated The maximum concentrations of heavy mainly from domestic and industrial metals were recorded in both soil and grasses discharges, gas production plant, in the traffic congested area and areas where agriculture and shrimp farming. rapid industrialization and urbanization take place. ✓ Higher concentrations of Cd (.07) and Pb (0.75) µg/g were recorded from Bay of Bengal coast that exceeded the Environmental Quality Standards of The higher concentration of Pb and Cr in Bangladesh (Cd: 0.05 and 0.10 µg/g). vegetables (Green arum leaves, jute leaves, water spinach, bottle gourd, wax gourd and ✓ Millions of the trees and people in sweet gourd collected from industrial area Sundarbans are being affected by heavy (Nasirabad, Agrabad, Vatiary and metal contamination. Chalkbazar). Heavy Metal concentration of Dhaka metropolitan city Thank you…