Chemical Dangers and Their Health Effects
What is Formaldehyde?
Formaldehyde is a colorless, unstable gas with a suffocating odor. It is used as a fumigant, disinfectant, herbicide, germicide, fungicide, and insecticide; in resins; synthetic fabrics, dyes, and explosives; rubber preservatives and coatings; in chemical analysis and synthesis; preservation of biological specimens and embalming; in drilling mud, photographic developers, and fertilizers. Formaldehyde can be an ingredient in many household products, including shampoo, hair creams and lotions, skin cleansers, nail polish and hardeners, dishwashing liquids, make-up, and as an additive for wrinkle-free fabrics. Exposure to formaldehyde occurs by vapors released by commonly used pressed woods and urea-formaldehyde insulation, polluted urban air, petroleum combustion, wood burning stoves, and smoking. Occupational exposures to formaldehyde have been associated with menstrual irregularities, birth defects and chromosomal changes.
What is Polyvinyl chloride?
Polyvinyl chloride, commonly abbreviated PVC, is a widely used thermoplastic polymer. In terms of revenue generated, it is one of the most valuable products of the chemical industry. Around the world, over 50% of PVC manufactured is used in construction. As a building material, PVC is cheap, durable, and easy to assemble. In recent years, PVC has been replacing traditional building materials such as wood, concrete and clay in many areas. Despite the fact that PVC production negatively affects the natural environment and human health, it is still widely used.
Polyvinyl chloride is used in a variety of applications. As a hard plastic, it is used as vinyl siding, magnetic stripe cards, window profiles, gramophone records (which is the source of the term vinyl records), pipe, plumbing and conduit fixtures. The material is often used in Plastic Pressure Pipe Systems for pipelines in the water and sewer industries because of its inexpensive nature and flexibility. PVC pipe plumbing is typically white, as opposed to ABS, which is commonly available in grey and black, as well as white. UPVC can sometimes be used as bulletproof glass for a cars window as it is very hard and thick. It can be made softer and more flexible by the addition of plasticizers, the most widely-used being phthalates. In this form, it is used in clothing and upholstery, and to make flexible hoses and tubing, flooring, to roofing membranes, and electrical cable insulation.
What is Acrylonitrile butadiene styrene?
Acrylonitrile butadiene styrene, or ABS, is a common thermoplastic used to make light, rigid, molded products such as piping, musical instruments, golf club heads, automotive body parts, wheel covers, enclosures, protective head gear, vballs [reusable paintballs], and toys including LEGO bricks. In plumbing, ABS pipes are the black pipes (PVC pipes are white) and also in Plastic Pressure Pipe Systems. ABS plastic ground down to an average diameter of less than 1 micrometer is used as the colorant in some tattoo inks. Tattoo inks that use ABS are extremely vivid. This vividness is the most obvious indicator that the ink contains ABS, as tattoo inks rarely list their ingredients.
It is a copolymer made by polymerizing styrene and acrylonitrile in the presence of polybutadiene. The styrene gives the plastic a shiny, impervious surface. The butadiene, a rubbery substance, provides resilience even at low temperatures. Production of 1 kg of ABS requires the equivalent of about 2 kg of oil for raw materials and energy. It can also be recycled.
ABS: Environmental Advantages:
More about Formaldehyde:
Formaldehyde is an industrial chemical used widely in industry to manufacture building products, other chemicals, and household products. In the home, formaldehyde is used as a coating or adhesive and comes in many synthetic resin mixtures. Some of the more common synthetic resins are phenol-formaldehyde (PF), malamine-formaldehyde (MF), and urea-formaldehyde (UF). UF is highly water-soluble and therefore is the most problematic mixture for indoor air pollution.
Common Sources
Formaldehyde synthetics are common indoors in composite wood products. Mobile homes are especially at risk for indoor formaldehyde pollution because of their abundance of composite wood in construction and relatively compact interior space. Formaldehyde gas can also be released into the air by burning wood, natural gas or kerosene, automobiles, and cigarettes. It can off-gas from materials made with it and it may also occur naturally.
Pressed wood-products which may contain formaldehyde include particle board (used in sub-flooring and shelving), hardwood plywood paneling (used in decorative wall covering, cabinets and furniture), and medium density fiberboard (used in drawer fronts, cabinets and furniture tops). Medium density fiberboard is especially problematic because it contains between 2 and 4 times as much urea-formaldehyde as common particle board.
Other sources include preservatives in some paints, chemical coatings (such as those found in the permanent press quality applied to draperies and fabrics), and the finish texture used to coat some paper products.
All of these formaldehyde mixtures will release dangerous formaldehyde gas into the air unless they are properly sealed. During warmer months, problems with formaldehyde can be especially serious as an increase in temperature of 5 to 6 degrees Celsius can double the gas's concentration. Further, an increase in relative humidity from 30% to 70% can also cause the gas concentration to nearly double. If both temperature and humidity increase, the concentration of gas can rise to five times its original amount.
Health Effects
Early health symptoms of formaldehyde in the home include eye, nose, and throat irritation as well as coughing and breathing difficulties. If the problem reaches a serious level, asthma attacks, nausea, vomiting, severe headaches, and nose bleeds can occur. The effects of short-term exposure are relatively small, as the health problems usually disappear once the pollutant has been removed. However, long-term exposure increases a person's sensitivity to the gas, increasing the probability of health risk. Studies have shown that persons in high contact with the gas over a long period of time (such as biological scientists or morticians) experience a high risk of acquiring cancer. Those who have worked with or lived around the gas for 10 or more years are considered at high risk.
Formaldehyde has been known to cause cancer in laboratory animals and could possibly cause cancer in humans. There is no known maximum threshold level and no known level below which there is not a threat of cancer. The risk of getting cancer from formaldehyde depends upon the amount and duration of exposure.
Prevention
In wood products, the easiest way to avoid problems with formaldehyde is to ask about the content of formaldehyde in pressed wood products including building materials, cabinets, and furniture before you purchase them. Try to avoid any products with urea-formaldehyde in them. There are plenty of building materials available which are formaldehyde free and exterior grade plywood can be used as a substitute for particle board. Although the exterior plywood may contain formaldehyde in some form, urea-formaldehyde is not used in exterior products and UF is the most problematic form of synthetic formaldehyde. Exposure may be limited by purchasing products labeled as low-emitting or wood products made from phenol formaldehyde, exp. OSB - oriented strand board or softwood plywood.
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