Lead levels in gasoline

Lynam DR, Pfeifer GD. 1988. Effects of decreasing lead exposures from gasoline and other sources on blood lead levels in man. Third Chemical Congress of North America held at the 195th American Chemical Society Meeting, Toronto, Ontario, Canada, June 5-10, 1988. Abstr Pap Chem Congr North Am 401-404. 

Laidlaw Filippelli (2008), Laidlaw et al. (2005), and Filippelli et al. (2005) have demonstrated that seasonal variations in children s blood lead levels In Syracuse, Indianapolis and New Orleans could be predicted using soil moisture and atmospheric variables suggesting that resuspension of urban soils contaminated by past use of leaded gasoline and paint were causally related to seasonal variations in blood lead. These papers concluded that urban lead contaminated soil was being re-suspended when soils were dry in the summer and autumn when... 

Sweden s crusade against the use of certain heavy metals provides a recent example of a blatant failure to observe the EU Commission s first requirement of proportionality of measures to achieve the appropriate level of protection. Many of the proposed restrictions cannot be expected to improve human health at all, or to have significant beneficial effects on the environment. During the last decades, lead levels in the blood in the Swedish population, including children, have steadily decreased, mainly as a result of the phasing out of leaded gasoline,41 and they are now similar to... 

The majority of 1,2-dichloroethane released into the environment enters the atmosphere from its production and use as a chemical intermediate, solvent and lead scavenger in gasoline. It has been detected at low levels in ambient and urban air, groundwater and drinking-water samples (United States National Library of Medicine, 1997). 

A compilation of available lead retention data is given in Table III, indicating only the most important conditions of a given test, where the information was available. With the exception of the work with pelleted vanadia catalysts (14), all the data pertain to lead levels in the range of 0.01-0.5 g Pb/gal, which was the range of interest in the years from 1972 to 1975, when the limits for contaminant levels in gasoline compatible with catalyst operation were actively considered. The data in the table cover an extremely wide set of conditions and include laboratory simulation, dynamometer, and vehicle fleet tests. Nevertheless, with a few exceptions, the lead retention falls within a relatively narrow band between 13 and 30%. 

The relative contribution of mobile source emissions to atmospheric lead levels over the next decade is expected to decrease slightly for two reasons (1) the Federal government s imposition of a phasedown of lead content in gasoline, as called for in regulations promulgated in September 1976 (43) and (2) the incompatibility of leaded gasoline and the catalytic converter introduced in late 1974 for control of regulated (HC, CO, NO,) pollutants (44,45). 

Since lead-containing antiknock additives of leaded gasolines rapidly destroy the activity of the catalytic emission control systems, unleaded gasolines have had to be used in automobiles fitted with this or related systems. However, since using this fuel modification also eliminates one of the main sources of lead emissions to the atmosphere, this trend also has a highly favorable additional impact [11, 12]. Before unleaded gasolines were on the market, it was common to find high lead levels in the core areas of busy cities... 

Typical catalyst poisons are lead and phosphorus. Lead is present at very low levels in unleaded gasoline. Typical lead levels are 0.003 g/gal although 0.05 g/gal is the maximum allowed lead level in unleaded fuel. Lead is not believed to be a major catalyst poison at the 0.003 g/gal level. On the other hand, use of leaded fuel will poison three-way catalysts, and catalyst activity is not fully recovered upon changing back to unleaded fuel. Figure 8... 

Since the 1970s, the lead level in rehned products in Canada and the U.S.A. has decreased substantially. Use of leaded gasoline in cars was completely banned in Canada and the U.S.A. in 1990 and 1996, respectively. 

Slovak Republic in the framework of the PHARE Project (1996-1997) (Table 7). Considering the situation in Slovakia, all the mean levels from all the sampling sites were below the annual National Ambient Air Quality Standards (0.5 p.g/m ) and guideline by WHO. Comparison with typical values for atmospheric lead levels in Europe indicates that, in general, the levels measured in Slovakia are at the lower end of typical European levels (Ursmyova and Hladikova, 1998a). Cities in Slovakia show the relationship between the decreasing use of lead in gasoline and the decline in airborne lead concentrations (Fig. 2) (Violova et al., 1997). 

Figure 2 Lead levels in Americans blood dropped as leaded gasoline was phased out.

Figure 3. Average blood lead levels in the United States dropped dramatically in the late 1970s when catalytic converters were introduced and leaded gasohne started to be phased out of use (16, 20). Unfortunately, although leaded gasoline is no longer used in the United States today, there is still residual lead contamination in the environment and in our blood.

Freije, A.M., and M.G. Dairi. 2009. Determination of blood lead levels in adult Bahraini citizens prior to the introduction of unleaded gasoline and the possible effect of elevated blood lead levels on the serum immunoglobulin IgG. Bahrain Med. Bull. 31(l) l-8. 

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