Pilot studies on regional lead levels in soilsAnalysis of Lead Concentration at Varying Elevations
Lead is a metal commonly found in soil. However, when lead becomes heavily concentrated in an area it can begin to contribute to numerous health effects. These health effects could include brain damage, nervous system damage, developmental defects, hearing loss, and in the most serious cases coma, convulsion, and death. The US standard for lead concentration in soil os 400ppm (Kaiser et. al. 2001). Blood lead levels over 10 µg/dL can be hazardous to a child's health. Children the ages six and under are more susceptible to these described health defects (Lead Poisoning: What Every Parent Should Know). This experiment was designed in order to answer the following question: How does the concetration of lead in soil change in relation to elevation? With this data a risk assessment could be made for citizens living at different elevations throughout the city of Meadville. After 1979 the United States started to phase out the production and consumption of leaded gasoline. Over the past decades leaded gasoline has been almost eliminated. In 1986 the amount of lead in gasoline was reduced to 0.1 g/gallon. Unleaded gasoline today is allowed to contain only .05 g/gallon (Leaded Gas Phaseout). However, the lead that was originally deposited from automobiles burning leaded gasoline can still be found in the soil today. We tested the lead levels at different elevations throughout the city of Meadville. The samples were taken from residential areas and by the roadside of schools and playgrounds. Going into the experiment two hypotheses were drafted. The first one stated: with an increase of elevation there would be an increase in lead concentrations in the soil. This was assumed as a result of cars emitting more leaded emissions as they strained to climb up the hill. As an automobile goes uphill it requires greater energy and therefore would require a higher consumption of the gasoline. The other hypothesis was as the elevation decreased there would be a higher lead concentration. Meadville receives a large amount of acid rainfall each year. It was suspected that this could cause lead to migrate down the slope with the runoff. No previous studies could be found in relation to our particular study so no conclusive predictions could be made. Lead Analysis of Playgrounds in the Meadville Area
Lead is a highly toxic metal that naturally exists in small amounts in the environment. Since the beginning of civilization, when adverse health effects were unknown, humans have utilized lead in various activities ranging from water containment to leaded gasoline. It wasn't until the 1950's that awareness of hazards associated with exposure to this metal became widely known. (ASTDR) Exposure to lead poses a serious health risk to children and adults. However, because of child behavior and physiology, children are more susceptible to increased health risks from exposure. (ASTDR) Children, which take in more food and water per body weight than adults, have a greater tendency to come into contact and ingest soil particles and paint chips that contain lead. Many children exhibit hand-to-mouth behaviors, thumb sucking or repeated eating of nonfood items which makes them at higher risk for ingesting contaminants. (Waggett) Infants and toddlers also spend more time on the ground which may increase their chances of coming into contact with lead in soil because of crawling or playing on the ground. Absorption of lead into the blood stream may be from five to ten times greater in young children who are also more sensitive than adults to elevated blood lead levels because they are still developing. (ASTDR) In adults, 99% of lead may leave the body as waste yet in children only 32% leaves, which shows a cumulative effect in the body. Several studies have demonstrated damage in lead-exposed children with blood lead levels as low as 10 to 14 µ/L . (ASTDR) The federal government considers blood lead levels at 10 µ/L or above to be a health concern for young children. These levels have been linked to behavior and learning problems such as poorer vocabulary, longer reaction times and poor hand-eye coordination. Damage to the brain and nervous system are also apparent as well as slowed growth, hearing problems, and even death. (CSPC) Following the elimination of leaded gasoline in the 1970's, lead in paint, and residual amounts in soils from flaked paint or leaded gasoline became the primary sources of human exposure to lead. (ASTDR) This metal had been used extensively in oil-based paint used for residential building structures prior to 1978 when lead paint was banned in the United States. (Waggett) Up until the 1950's, lead-based paints contained greater than 45% lead. (ASTDR) In 1971, the federal government reduced the amount of lead allowed in paint to 1%. (Waggett). Following the ban in 1978, only 0.06 percent or 5,000 ppm was allowed and 400 ppm for soil (Kaiser). This is currently the standard for lead restrictions, yet many older structures that existed before the ban presently contain higher levels of lead. (CPSC) Studies performed by the Consumer Product Safety Commission as well as state and local governments have shown that, while lead paint on residential buildings is the main source of exposure to children, playgrounds pose an additional risk to children primarily 6 years and younger. Metal playground equipment that was built before the 1978 ban on lead paint has been found on numerous playgrounds across the United States. (CSPC) The equipment was originally painted with lead paint. In an attempt to minimize exposure to lead, some playground equipment may have been painted over to cover the hazardous paint. (ROSPA) Over time, normal wear and exposure to natural elements such as sunlight and rain has caused the paint to chip which may then be ingested by small children or flake into the soil. (CSPC) While the levels on the playgrounds themselves may not be toxic, the cumulative nature of lead may contribute to the overall health risk. (ASTDR) On a local level, sources have indicated that playgrounds in and around Meadville, Pennsylvania were built prior to the lead paint ban in 1978. The purpose of this study was to determine if painted metal structures existing on playgrounds in the Meadville area contained lead which may be a potential health hazard to children. Due to upgrading and repainting of equipment, which minimizes exposure to lead, the paint samples should contain less lead than the surrounding soil which should accumulate lead and show a residual effect. The residual lead in the soil of older playgrounds should be higher than in the newer playgrounds which should not have as much exposure to lead as older playgrounds. Lead Concentrations in Soil and Paint of College Owned Houses
Lead is a heavy toxic metal that is found naturally in ore. This element was used primarily in paint and gasoline. Lead in paint was particularly useful because it extended the life of the paint and also acted as a fungicide. Nonetheless, in 1978 lead was banned from the production of paint and gasoline because of documented health effects. In spite of the ban, lead is still a problem facing many urban and industrial cities. Most urban homes were built prior to 1978 and have been poorly maintained, suggesting that lead is still very prevalent in these homes. In older homes lead may still be found in the paint, dust, soil, and pipes. A person can increase their blood lead levels by inhaling lead dust, or by consuming soil or paint chips containing lead. There are numerous health concerns that arise when a person has elevated blood lead levels. For children, lead poisoning can be particularly harmful because they are still developing. Adults are also very vulnerable to lead poisoning. According to the National Safety Council, dangers to adults have been recognized since the 18th century. In fact, Benjamin Franklin made note of the extreme danger of lead poisoning. During the 1900s, the occupational exposures to lead in the US were so common, that only deaths were recorded. Currently, the US Department of Housing and Urban Development (HUD) estimates that about 38 million homes in the US still contain some lead paing (NCS, 2004). Adults can be affected by heightened blood lead levels, which may result in reproductive problems, high blood pressure, digestive problems, nerve disorders, concentration problems, and joint and muscle pain. Adults exposed to lead at work, such as painters, agricultural workers and maintenance personnel, are at high risk for lead exposure. Homeowners who garden around their house are also at risk. Lead in the soil often occurs due to peeling paint that falls to the ground. This lead can get into the dirt where homeowners garden, relax, or play around their house. There is a possibility that these homeowners will come in contact with the leaded soil and absorb it into their blood stream. Since each side of a house experiences different weathering conditions, the lead levels in the soil may vary depending on the side of the house. Our independent research project examined the levels of lead in the soil and paint of college owned houses. Considering students study and play outside their houses, their exposure seemed high. Therefore, we decided to test five special interest houses for their lead levels. The Lighthouse, Faith and Justice house, Writer's house, German house, and Eco house were targeted. We hypothesized that each house would have varying lead concentrations due to their location and the date of their construction. Then based on the analysis of the soil we predicted that the paint would be the primary cause of lead presence. Overall, our objectives for this experiment were to determine the lead concentration in the soil on the North, South, East, and West side of each house. We also wanted to compare the results of the total lead concentration from house to house. Finally, based on soil concentrations, paint samples will be taken from the significant houses. Soil Lead Analysis of Crawford County Roads
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