Consumption , lead statistics

One study has reported effects on neurobehavioral function in lead-exposed workers at mean PbB levels of 50 pg/dL (Williamson and Teo 1986). Neurobehavioral function was measured using tests that are based on information processing theory in 59 lead workers and 59 controls matched for age, type of job, time on the job, education level, smoking history, and alcohol consumption. Statistically significant decreases in the lead-exposed workers were seen for critical flicker fusion reaction, simple reaction time, tracking speeds, hand steadiness tests, and sensory store memory. Sensory store memory speed showed a low but statistically significant correlation with PbB concentrations. Measurements of neurobehavioral function seemed well chosen, and repeated measures with associated appropriate statistics were used. 

Chronic lead nephropathy in moonshiners, more often than not, is accompanied by gout and hypertension, in accord with 19 century descriptions of plumbism and reports from Austraha [1]. A statistically significant odds ratio of 2.4 has been reported for moonshine consumption and end-stage renal disease, suggesting a causal association with lead in fhe absence of symptomatic lead poisoning [31]. 

There are certain essential differences between solid state reactions and reactions involving gaseous or liquid phases. In the latter case, the kinetic motion of the reactant molecules ensures that they are available to one another for reaction under conditions which can be defined by statistical laws. Solid state reactions occur between apparently regular crystal lattices, in which the kinetic motion is very restricted and depends on the presence of lattice defects. Interaction can only occur at points of contact between the reacting phases and is therefore dependent on particle size and particle size distribution. The factors which govern the rate of a solid state reaction are (/) the rate of the boundary phase processes which lead to the consumption of the original lattices, and (ii) the rate of particle transfer through the product layer. 

American Bureau of Metal Statistics, 33 Rector St., New York, Yearbook, annual, 1921-. Production of certain copper and brass products. Consumption of copper, lead, and zinc by fabricators. 

Many lead-containing products, including leaded glass, can be recycled and provide another source of material to supplement the naturally occurring minerals. The processing required to produce metallic lead and lead oxides are outlined in Sect. 3. Descriptions of the most important sources of lead and statistics on lead production and consumption are also presented. 

Additionally to the measurement as described above, a free selected number (mostly 3-11) of channels is measured (scanned) and the highest value in this window is taken as Neff. This evaluation procedure can be well applied to concentrations clear above the detection limit (by at least a factor of 100), otherwise the counting statistic will influence the "highest value" and also lead to a higher relative standard deviation (3-5%). On the other hand, the advantage is a relatively fast measurement and therefore a low sample consumption. Especially in case of biological and medical samples, when only small... 

WRc performed a detailed study and a statistical assessment of water use in the United Kingdom in relation to the problem of lead monitoring at the consumer s tap (Bailey et al, 1986b). The study covered 100 households in 22 districts in England, Scotland and Wales. The consumption of water, with distinction between potable and non-potable use, and time of use, was recorded for each household during one week. The results of the study are summarized in Table 3.1. 

When postural control was measured in 63 lead battery workers (mean past BLL 38 pg/dL), there were statistically significant increases in mean body oscillations with eyes closed and head tilted forward (Ratzon et al. 2000). Partial correlation after adjirstment for education, coffee consumption, hours of sleep, and estimate of health was significant only for total lead exposure and increased body oscillations with head tilted forward. To maintain balance, lead-exposed workers required increased oscillations when visual and vestibular inputs were altered. 

Primary U.S. and world lead production levels, along with statistics for secondary production, U.S. imports and exports, and estimates of apparent U.S. consumption are set forth in Table 3.2. From 1900 to 1923, the USGS provided production rates via the series. Mineral Resources of the United States. From 1927 to 1934, the production figures were produced by the U.S. Bureau of Mines, which became the sponsor of Mineral Resources. From 1932 to 1994, the Bureau became the principal source of U.S. lead production data as the annual Mineral Yearbook series. This continued until 1994, the last year in which the Bureau of Mines existed as a discrete governmental agency. Post-1994, the sources include figures of the USGS, which took over the metal production estimation tasks of the former Bureau in 1995. 

The recent economic growth in certain countries which formerly had modest lead consumption levels appears to have propelled world lead production and consumption upward, which is evident in statistics for the most recent years indicated in Table 3.3. This particularly appears to reflect the rapid economic growth and commodity demands in China for lead for such uses as lead storage batteries. 

National and International Dietary Pb Surveys A number of dietary Pb surveys have been carried out in the United States and around the world. Summaries of these surveys are presented in this section. Some surveys have simply reported descriptive statistics for lead concentrations in dietary groups and levels of Pb in individual food components within those groups, e.g., measured Pb levels in cereals as a group. Other surveys have reported Pb levels in dietary components and coupled these with consumption patterns to provide intakes of food Pb in some time frame, typically as daily total intakes. Some survey reports have mainly concerned themselves with total dietary Pb intakes. This chapter confines itself to Pb levels in foods and presents intakes and uptakes in the context of human exposures in later sections. 

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