HazardousandToxicWaste有害有毒废弃物.ppt

Hazardous and Toxic Waste,Environmental concerns and heath problems of hazardous waste; toxicity and its measurement,Learning outcomes,When you have studied the information in this lecture you should be able to: Define solid waste and compare solid waste disposal methods Identify the sources of toxic waste Identify major environmental toxins Explain effect of toxic pollutants Explain how waste is classified,Topics,Solid Waste Toxicity Classification and Characteristics of waste Pharmaceutical Wastes Hazardous waste management,What is Solid Waste?,The term solid waste means any refuse, sludge from a waste treatment plant, water supply treatment plant, or air pollution control facility and other discarded material, including solid, liquid, semisolid, or containing gaseous material resulting from industrial, commercial, mining, and agricultural operations, and from community activities, but does not include solid or dissolved material in domestic sewage.,Types of Solid Wastes,Municipal Solid Waste (MSW)- what “we” produce daily Hazardous Waste A subset of solid waste Industrial Waste Agricultural Waste Mining Waste,Medical Waste Air Pollution Control Residuals WWTP residuals Organic and bacteria residue from waste WTP residuals Mainly metallic salt,How Do You Manage Solid Waste?,Prevent Minimize Recycle Compost Waste to Energy Landfill,Waste Prevention and Source Reduction,Re-engineering of a product or process Use less packaging Re-use Do not let the material enter the waste stream in the first place Consume less materials Example: Double-sided printing,Recycling,Taking a discarded product and using to make a new product Same as first one An entirely new product Examples?,Recycled municipal solid waste components,Fibers Newspaper Cardboard Office Paper Containers Glass Plastic Metal,Major Markets: New paper products, other products (e.g. insulation),Recycled municipal solid waste components,Fibers Newspaper Cardboard Office Paper Containers Glass Plastic Metal,Commonly recycled plastics 再生塑料,PET (polyethylene terephthalate) Original use: Beverage bottles Recycled use: Carpet fibres, insulation HDPE Original use: milk, juice bottles Recycled use: oil and soap bottles, drain pipes,PVC Original use: food wraps, bottles Recycled use: floor tiles, traffic cones LDPE Original use: bin bags, wraps Recyled use: irrigation pipes, oil bottles,Composting 堆肥,A form of biological treatment Aerobic 有氧 Diverse Fungi, bacteria, insects, worms Anaerobic 厭氧 Fairly well defined groups of bacteria Commonly applied to bio-solids, garden waste and agricultural waste Less commonly applied to MSW,What types of solid waste are produced as a result of pharmaceutical production?,Toxicity,Measure the degree to which something is toxic or poisonous Depends on dose, duration and route of exposure Exposure routes Dermal Inhalation Ingestion,Toxins,Term toxin usually used when talking about toxic substances produced naturally A toxin is a poisonous substance of microbial, vegetable or synthetic origin that reacts to kill cells, alter growth or kill the organism,Plant Toxins did you know?,Stones and pips of apricots, plums, cherries, peaches, apples and pears all contain glycosides which if eaten release potentially lethal doses of cyanide Rhubarb contain large quantities of oxalic acid, which interferes with calcium absorption,Plant Toxins did you know?,Many plants of the Brassicia (cabbage) family contain goitrogens goitrogens interfere with the production of thyroid hormones by preventing iodine incorporation Potatoes which have turned green, sprouted or have developed a bitter taste are toxic because they contain solanine. Defence mechanism for the plant (e.g. anti-fungal properties) Honey from rhododendrons is highly toxic,Toxins in Nature did you know?,The liver of the blow fish (puffer fish) is extremely poisonous There is cyanide in cassava and almonds (there are official limits for cyanide concentration in marzipan).,Belladonna, strychnine and aconite: three of the most poisonous plants in the world. One of these deadly alkaloid toxins was used to murder Alexander the Great.,Cherry lauryl: leaves can cause cyanide poisoning. Often found in hedges and in parks.,Amanita phalloides, the death cap mushroom, is a cause of acute liver failure,Types of toxic entities,Chemical Example; Heavy metals, pesticides Biological threshold value can be a single organism Plant toxins- yew tree Animal toxins snake bites Physical Heat and cold, IR and UV radiation, X rays and gamma rays, alpha and beta rays,Environmental Toxins,Some are designed to be toxic (e.g., pesticides, herbicides), while others are used for industrial purposes. Most toxins can be categorized into the following groups. Dioxins and Furans PCBs (Polychlorinated biphenyls) HCB (hexachlorobenzene) Pesticides Heavy Metals,Dioxins and Furans,Dioxins and Furans are chlorinated chemicals that originate from various sources, including waste incinerators, waste water from paper industry and by-products from general industry. The term Dioxins include 75 polychlorinated dibenzo-p-dioxin (PCDD) and 135 polychlorinated dibenzo furan (PCDF) substances. Of these, 17 are toxic in very small amounts.,PCBs (Polychlorinated biphenyls),PCBs were used for many years in transformers, capacitors and certain building materials. Although PCBs are not produced today, they are still found in the environment from the disposal of products containing PCBs.,Hexachlorobenzene: HCB is a by-product from chlorine gas and pesticide production. Pesticides Pesticides include DDT dichlorodiphenyltrichloroethane (insecticide), toxaphene, chlordane, lindane and HCH. Insecticides include Organophosphorus and carbamate compounds (anticholinesterase compunds =nerve agents) and Chlorinated hydrocarbons,Environmental Toxins,Heavy Metals The most common heavy metals disposed of by industry are Mercury, Lead, Chromium, and Arsenic. Heavy metals are also found naturally in the environment.,Environmental Toxins,Biomagnification and Bioaccumulation,Bioaccumulation 生物蓄積性 is the increase in concentration of a pollutant from the environment to the first organism 有機體 in a food chain 食物鏈, it refers to how pollutants enter the food chain Biomagnification 生物放大 is the increase of a pollutant from one link in a food chain to another. It refers to the tendency 傾向 of a pollutant to concentrate 集中 as they move from trophic level 營養水平 in an ecosystem 生態系統 to the next.,Biological Magnification 生物 放大 process whereby substances move up the food chain, work their way into rivers or lakes, and are eaten by aquatic organisms such as fish The fish in turn are eaten by large birds, animals or humans. The substances become concentrated in tissues or internal organs as they move up the chain E.g. pesticides or heavy metals Bioaccumulants: substances 物質 that increase in concentration in living organisms 增加 濃度 生物 as they take in contaminated air, water, or food Why do certain substances bio-accumulate? They are very slowly metabolized 代謝 or excreted 排泄.,Bioaccumulation 生物蓄積性 occurs within a trophic level and is the increase in concentration of a substance in certain tissues of organisms bodies due to absorption from food and the environment由於從食物中吸收和環境 Bioconcentration 生物富集 occurs when uptake from the water is greater than excretion 從水中吸收大於排泄. Thus bioconcentration and bioaccumulation occur within an organism, and biomagnification occurs across trophic (food chain) levels.,First synthesized by German chemist in 1874,in 1930s Paul Muller discovered that it was a potent insecticide,During WWII it was used on soldiers and refugees to kill lice,Muller received a Nobel Prize for his discovery,By the 1960s, DDT had become a household item, the worlds most used pesticide, and was considered harmless,Example of Bioaccumulation DDT (dichlorodiphenyltrichloroethane),Gulls, which feed on clams, may accumulate DDT to 40 or more times the concentration in their prey. This represents a 400-fold increase in concentration along the length of this short food chain.,Example of Bioaccumulation - DDT,Water 0.000002 ppm,Biomagnification of PCBS in aquatic food chain,Endocrine Disruptors,Endocrine Disruptors 內分泌 干擾物 : these are oestrogen mimic chemicals that interfere with the normal function of the endocrine system (glands including thyroid, adrenals, ovaries, testicles) Mimic hormone, trigger identical response, block a hormone Do not follow the normal dose/response curve Active at much lower doses, especially in the fetus and newborn Estradiols, progesterone, testosterone Natural and synthetic hormones, pesticides, industrial chemicals used in the manufacture of paints and detergents, phthalates from the plastics industry, and many pharmaceuticals,Examples,Estradiols Polyphenols DDT,Progesterone Testosterone,Infertility Hormonally triggered human cancers Neurological disorders in children Hyperactivity Attention deficit Developmental & reproductive problems in wildlife,Effects of Endocrine disruptors,Endocrine disruptors,Can cause congenital mis-programming of the endocrine system Can reduce fertility, especially in females Risk to long-term abundance and viability of wildlife species Enter the environment from municipal, agricultural, and industrial wastewaters.,Dose and dose-response,Dose is the actual amount of a chemical that enters the body Acute (short time period) Chronic (long time period) Dose-response relationship between exposure and health effect,Dose and dose-response,Threshold dose 閾值劑量 no observed effect level. This is the level below which adverse effects are not seen in the population LD50 median lethal dose of a toxin, radiation, or pathogen is the dose required to kill half the members of a tested population Individual susceptibility and sensitive sub-population,Level mg/kg,100%,50%,LD 50,LD50 curve,Toxicities LD50,Ethanol ORAL-RAT LD50 7060 mg kg-1 Ethyl Ethanol: 7,060 mg/kg = 7.1g/kg = LD50 i.e. about 7 bottles of wine will kill 50% of the rat population ORL-CHD LDLO 2000 mg kg-1 (lowest published lethal dose for a child),Toxicities LD50,Paracetamol Oral rat LD50: 2404 mg/kg In adults, single doses above 10 grams or 150 mg/kg have a reasonable likelihood of causing toxicity. Toxicity can also occur when multiple smaller doses within 24 hours exceeds these levels, or even with chronic ingestion of doses as low as 4 g/day, and death with as little as 6 g/day.,Ethanol: 10,000 mg/kg = 10g/kg = LD50 i.e. about 10 bottles of wine,Solid waste classification Regulatory basis,The European Waste Catalogue and hazardous waste list are used for the classification of all wastes and hazardous wastes in the EU EWC and Hazardous waste list are designed to form a consistent waste classification system across the EU.,In China: NCHW National Catalogue of Hazardous Wastes They form the basis for all national and international waste reporting obligations, such as those associated with waste licenses and permits, the National Waste Database the transport of waste,Solid waste classification Regulatory basis,Solid waste classification steps,Consult the Waste Management Act. lists the different categories of waste Consult the EPA document European or Chinese Waste Catalogue and Hazardous Waste List the origin of waste or type of waste. The Waste Catalogue gives information on acceptable test methods to determine the properties of the waste i.e. harmful, explosive, eco-toxic, toxic etc. The characteristics of the waste is measured against specific criteria.,Properties of waste,Explosive Oxidising Flammable Irritant Harmful Toxic Carcinogenic,Corrosive Infectious Toxic for reproduction Mutagenic Ecotoxic Residuary hazardous property,To classify waste as hazardous or non-hazardous, waste must be tested for these properties or analysed for waste components,Characteristic of Corrosivity,An aqueous solution having a pH 2 or 12.5 Examples: Primarily compounding chemicals Glacial Acetic Acid Sodium Hydroxide Hazardous waste number: D002,Characteristic of Toxicity,Approximately 40 chemicals meet specific leaching concentrations Examples of potential toxic pharmaceuticals: Arsenic m-Cresol Barium Mercury (thimerosal) Cadmium Phenylmercuric acetate Chloroform Selenium Chromium Silver Lindane,Preservatives: thimerosal & m-cresol,Heavy Metals: Selenium, Chromium and Silver,Examples of Pharmaceuticals Exhibiting the Characteristic of Toxicity,Characteristic of Reactivity,“Reactive hazard“ is used to refer to a substance that undergoes a violent or abnormal reaction in the presence of water or under normal ambient atmospheric conditions. Examples Ethyl ether, isopropyl ether, dioxane, tetrahydrofuran and many other ethers absorb and react with oxygen from the air to form unstable peroxides which may detonate with violence,Carcinogens,There are many natural carcinogens. Aflatoxin B1 黃曲霉毒素B1, which is produced by the fungus Aspergillis flavus growing on stored grains, nuts and peanut butter, is an example of a potent, natural microbial carcinogen. Certain viruses such as Hepatitis B B型肝炎 and human papilloma viruses 人類乳頭狀瘤病毒have been found to cause cancer in humans.,Aspergillis flavus,More Carcinogens,Benzene, asbestos 石棉, and the waste rock of oil shale mining 油頁岩 have all been classified as carcinogenic. As far back as the 1930s, industrial smoke and tobacco smoke were identified as sources of dozens of carcinogens, including benzyopyrene and tobacco-specific nitrosamines Reactive aldehydes such as formaldehyde also carcinogenic which is also a hazard in making plastics. Vinyl chloride, from which PVC is manufactured, is a carcinogen,Pharmaceuticals Entering the Waste Stream,Waste raw Materials from Manufacturing Process Wastage at the Distributor/ Pharmacy/Healthcare Facility Expired Pharmaceuticals Wastage at the Consumer Level Metabolites Entering Wastewater,Waste drugs from healthcare facilities,Sewer System Unused, partial IVs, including antibiotics Liquids Red Infectious Waste Sharps Containers, Bags Yellow or White Chemotherapy Sharps Containers, illegal dumps?,Source: Brown, Michael, “Drums of Death”, Audubon, 120 July 1980.,How is Pharmaceutical Waste Generated at a Healthcare Facility?,IV Preparation Spills/Breakage Partially Used Vials/Syringes If contaminated they are bio-hazardous Discontinued unused Preparations Discontinued undated Pharmaceuticals Patients personal medications Outdated Pharmaceuticals,Where is Pharmaceutical Waste Generated outside the industry?,Pharmacy Patient Care Units Hospitals Clinics Long Term Care Facilities Home Health Care Services,W