Lead in petrol

Morgan A, Holmes A. 1978. The fate of lead in petrol-engine exhaust particulates inhaled by the rat. Environ Res 15 44-56. 

Barrett, B. and R. Howells. 1984. Legal control of standards lead in petrol. Sci. Total Environ. 33 1-13. Barrett, J. and PJ. Livesey. 1983. Lead induced alterations in maternal behavior and offspring development in the rat. Neurobehav. Toxicol. Teratol. 5 557-563. 

Situated between the solid and gaseous states as the only non-metallic element liquid at ambient temperature, bromine is sandwiched in the periodic table between the ubiquitous chlorine and the rather rare iodine. In terms of production volumes it is neither a bulk commodity chemical like chlorine, nor a speciality chemical like iodine. And commercially, bromine is beset by uncertainty. Until the 1970s, the major market forbromine was in dibromoethane - a co-additive for leaded petrol. The phase-out of lead in petrol could have spelled the collapse of the bromine industry, but alternative bromine markets developed and the industry both rationalised and flourished. However, although world bromine production continues to increase slowly, fresh environmental concerns have emerged and the industry is once more under threat. Details are given. 19 refs. 

What are things made from We have become a society obsessed with questions about composition, and for good reason. Lead in petrol shows up in the snow fields of Antarctica mercury poisons fish in South America. Radon from the earth poses health hazards in regions built on granite, and natural arsenic contaminates wells in Bangladesh. Calcium supplements combat bone-wasting... 

In January 1986, the permissible concentration of lead in petrol in the UK was reduced by 62%, from 0.4 to 0.15 g 1 1. Regular measurements of PbA in 1985 and 1986 have been reported from 26 urban locations (Mclnnes, 1986 Jensen Laxen, 1987 Pattenden Branson, 1987 Page et al., 1988). The mean percentage fall in PbA was 49.4 (s.e.) 1.9%. This is in accordance with other evidence that before 1986 lead from petrol contributed about 80% of airborne lead. 

In Table 7.4, the percentage reductions in PbB in 1985/6, coincident with the reduction in lead in petrol, for the exposed groups are shown. Assuming 6.2% reduction from other causes, the percentage reductions associated with the change in petrol, are as shown in the second column. 

The third column gives an approximate estimate of the standard error of the excess reduction, taking into account only statistical variations. The final column of Table 7.4 gives the excess reductions in terms of PbB. Since a reduction in petrol lead of 60% gave a reduction in PbB of exposed men and women of 4%, the conclusion might be drawn that lead in petrol contributed 7% of PbB before the reduction. Similarly, for traffic police and children, it contributed 20% and 16% respectively. These results are broadly compatible with the results of the Isotopic Lead Experiment, taking into account the special factors tending to increase exposure to PbA in Turin. 

The 26 stations mentioned above include both roadside and urban background locations, and gave mean PbA levels of 0.70 before and 0.35 fig m-3 after the change in petrol. Assuming that a reduction of 0.35 jug m-3 resulted in the falls in PbA of the last column of Table 7.4, /3 can be estimated as 7, 39 and 25 m3 kg-1 for exposed men and women, traffic police, and children respectively. Thus the falls in PbB in these subjects, coincident with the reduction in lead in petrol, are reasonably consistent with expectations based on the inhalation experiments with 203Pb and the Isotopic Lead Experiment in Piedmont. 

Jensen, R. A. Laxen, D.P.H. (1957) The effect of the phase-down of lead in petrol on levels of lead in air. The Science of the Total Environment, 59,1-8. 

The above calculations estimate that for a typical adult in a developed country, daily uptake of lead from air, diet, and drinking water is, respectively 1.4 pg, 6 pg, and 1.1 pg. Exposure to lead from all of these sources has fallen rapidly over the past 20-30 years. Figure 12 contrasts the temporal trends in use of lead in petrol (gasoline) and blood leads in the general population of the UK over the period when much of this decline took place. It is interesting to note that from 1971 to 1985 use of lead in petrol was relatively steady, but blood leads declined by a factor of more than two over this period mainly as a response to reductions in dietary exposure, particularly associated with the cessation of use of... 

Reduction of lead in petrol in the USA to less than i per cent in 1971 and then to 0.06 per cent in 1977 has had a dramatic effect on levels of lead in people in 1980, the average daily lead intake in male babies was 45 pg and 84 pg in adult men by 1990 these levels were down to about one-tenth. 

Shy CM. 1990. Lead in petrol The mistake of the XXth century. World Health Statistics Quarterly 43 168-176. 

A glas tube (diameter 0.8 cm), filled successively with the following reagents, was used as a reactor 3 cm of silver nitrate on diatomite (1 1), 2cm of sulphuric acid on diatomite, and 1 cm of disodium phosphate on diatomite. Each layer in the reactor was separated from the next with a small layer of diatomite brick. The reactor was placed before the separating column (LSP Twin-60). At room temperature 2-bromobutane is absorbed quantitatively by the layer of silver nitrate, and 1 -bromo-2-methylpropane does not react with it. The use of a reactor containing silver nitrate for absorbing dichloro-ethane and dibromoethylene in the GC analysis of methyl and ethyl compounds of lead in petrols using an electron-capture detector has been described [92]. 

Disregarding the presence of nitrogen oxides, sulphur-containing substances and compounds of lead in petrol, it is possible to write the following equation for the combustion... 

The lead oxide (PbO) formed, reacts with the halogen carriers (the co-additives) to form particles of lead halides- PbCh, PbBrCl, PbBr2- which escape into the air through the vehicle exhaust pipes. By this, about 80% of lead in petrol escapes through the exhaust pipe as particles while 15-30% of this amount is air borne. Human beings, animal and vegetation are the ultimate recipients of the particulate (Ademoroti, 1996). 

Nevertheless, considerable concern has been expressed about the pollutant nature of the exhaust products of leaded petrol combustion and about atmospheric lead levels. Atmospheric lead, derived in part from combustion of lead-treated petrol, is seen as being environmentally unacceptable and a potential health hazard, especially to children. In recent years, legislation has restricted the amount of lead in petrol in many countries. Table 2 shows the maximum lead content of petrol in several countries. 

Associated Octel. (1982). The Lead in Petrol Issue Reference Literature. (London Associated Octel)... 

F.O.E. (Price, B.) (1982). Lead in Petrol An Energy Analysis. (London Friends of the Earth)... 

In recent years there has been growing awareness of the hazards from lead in the environment. The permitted amount of lead in petrol is gradually being reduced, although the UK is lagging behind some other countries such as Germany and Japan in this regard. 

Each sample period made up of sequential 10-15 min samples. Individual samples show much wider range of concentrations, t At the time the max concentration of lead in petrol was 0.7 g dm". ... 

Figure 43.6 shows how the use of lead for storage batteries increased during the 20 year period from 1975 to 1994. This indicates a raised use of automobiles and other vehicles. In spite of that the usage of lead in many other applications has decreased as a result of environmental pressure. This is clearly manifested in the reduced shares of lead in petrol and in sheathed cables. Environmental actions have not resulted in decreased lead consumption but rather in a changed pattern, exemplified by the fact that, of all the lead used in the USA in 2001,96% was for storage batteries. 

Figure 43.6 The use of lead for different purposes in the West in 1975 and 1994. The increase in the share of lead for accumulators is obviously due to the increased total number of vehicles. In spite of that, lead in petrol has de-...

Facchetti, S., 1989. Lead in petrol. The isotopic lead experiment. Acc. Chem. Res. 22, 370—374. Facchetti S., Geiss F., 1982. Isotopic lead experiment status report. Commission of the European Communities, Publication No. Eur 8352 EN. CEC, Luxembourg. 

The amount of lead in petrol can also be cut down. The government has placed a limit on the amount of lead allowed per litre of petrol. But many people think lead is so dangerous that it should be banned from petrol altogether, and in some countries lead-free petrol is already on sale. 

Part of a demonstration against the use of lead in petrol. Lead is especially harmful to children. 

The general presence of a metal as toxic as lead in the urban environment has since attracted considerable attention and the possible effects of direct inhalation of lead discharged in motor vehicle exhausts are of interest to clinicians and public health authorities. Indeed, the implications for health of the presence of lead in petrol have become a concern of environmentalists and a major public issue. The quantity of lead directly dispersed as an atmospheric pollutant every year is enormous. The total world consumption of lead for use as lead alkyl additives to petrol was estimated at 350,000 tonnes in 1970, about 70 per cent of this amount being consumed in the USA [198]. Stoker and Seager [199] have estimated that about 180,000 tonnes of lead alkyls end up in the... 

Caplun E, Pettit D, Picciotto E (1984) Lead in petrol. Endeavor 8 135-144. 

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