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For six New Havent woody plant species, the mean lead concentrations for tissue produced in the preceding growing season exceeded most lead concentrations determined for trees in areas with geologic lead deposits or adjacent to primary highways. Preliminary estimates indicate that some New Haven plants have slightly higher than natural amounts of mercury. The burden of lead and the difficulty in removing it by washing suggest a potential for pathological significance.
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William H. Smith (1972) studied this question.
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