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<br /> 5. POTENTIAL FOR HUMAN EXPOSURE
<br /> anning foods in lead-soldered cans may increase levels of lead by 8-10-fold; however, the impact of
<br /> i nning appears to be decreasing as a result of a decrease in the use of lead-soldered cans. The use of
<br /> Vee-piece lead-soldered cans ceased in 1991; however, older lead-soldered cans may still be present in
<br /> me households. In 1974, for example, the lead level in evaporated milk in lead-soldered cans was 0.12
<br /> g/g, whereas in 1986, after these cans were phased-out, the lead level in evaporated milk dropped to 0.006
<br /> ; The
<br /> /g (Capar and Rigsby 1989). The lead content in canned foods dropped from an overall mean of 0.31
<br /> k m in 1980 to 0.04 ppm in 1988 (NFPA 1992). A 1982 Canadian study indicated average lead
<br /> y ncentrations in dairy milk to he 0.00112 yg/g, whereas lead levels in various infant formulas ranged from
<br /> 026 µg/g for bottled water to 0.0737 µg/g in infant formula powders (Dabeka and McKenzie 1987).
<br /> s ditional exposure to lead through dietary intake by people living in an urban environment is estimated
<br /> approximately 28 jug/day for adults and 91 µg/day for children, all of which can be attributed to
<br /> 1 (mospheric lead (dust). Atmospheric lead may be added to food crops in the field or garden (through
<br /> 1 take from soil and from direct deposition onto crop surfaces), during transport to market, processing,
<br /> J ad kitchen preparation (EPA 1986a).
<br /> d may leach from lead crystal decanters and glasses into the liquids they contain. Port wine which
<br /> ntained an initial concentration of 89 µg/L lead, was stored for 4 months in crystal decanters containing
<br /> p to 32?/ lead oxide. At the end of 4 months lead concentrations in the port were 5,3: 1, 3,061, and
<br /> a 162 µg/L in decanters containing 32"/,, 32"/.., and 24%, lead oxide, respectively. Lead was also found to
<br /> lute from lead wine glasses within minutes. Mean lead concentrations in wine contained in 12 glasses
<br /> t lse from 33 Ag/L initially to 68, 81, 92, and 99 µg/L after 1, 2, 3, and 4 hours, respectively (Graziano and
<br /> ium 1991).
<br /> s
<br /> i aking paint, paint chips, and weathered powdered paint, which are most commonly associated with
<br /> J teriorated housing stock in urban areas, are major sources of lead exposure for young children residing
<br /> these houses, particularly for children with pica (i.e., the compulsive, habitual consumption of nonfood
<br /> t ems) (Bornschein et al. 1986; EPA 1986a). Lead concentrations of 1,000-5,000 µglCM2 have been found
<br /> chips of lead-based paint (Billick and Gray 1978), suggesting that consumption of a single chip of paint
<br /> uld provide greater short-term exposure than any other source of lead (EPA 1986a). It is estimated that
<br /> tween 40 %, and 50"/c, of currently occupied housing in the United States may contain lead-based paint
<br /> exposed surfaces (Chisolm 1986).
<br /> d is also present in tobacco at concentrations of approximately 2.5-12.2 ug/cigarette, of which
<br /> k proximately 2-6% may actually be inhaled by the smoker (WHO 1977).
<br /> ses of lead poisoning have been related to less common sources of exposure. Illicit "moonshine" whiskey
<br /> de in stills composed of lead-soldered parts (e.g., truck radiators) may contain high levels of lead. Seven
<br /> 12 samples of Georgia moonshine whiskey had detectable levels of lead with a maximum concentration
<br /> 5.3 mg/L (Gerhardt et al. 1980). Use of lead ammunition may result in exposure to lead dust generated
<br /> ring gun or rifle discharge at levels up to 1,000 jug/M3 (EPA 1985c), lead pellets ingested or imbedded
<br /> °animals that are used as food sources, and lead pellets imbedded in humans from shooting incidents
<br /> ohnson and Mason 1984).
<br /> 1972, household dust samples taken near nonferrous ore smelters in EI Paso, Texas, which were known
<br /> emit 1,012 metric tons of lead per year, had lead levels of 22,191 µg/g (geometric mean) and 973 µg/g
<br /> .distances from the smelter of 1.6 km and 6.4 km, respectively (Landrigan and Baker 1981).
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