Environmental Engineering Reference
In-Depth Information
Table 3.1
Estimated turning points for various pollutants and studies
Pollutant
Study
Turning point ($)
Arsenic (concentration)
Grossman and Krueger (1995)
4 900
Biological oxygen demand
Grossman and Krueger (1995)
7 623
Chemical oxygen demand
Grossman and Krueger (1995)
7 853
CO (emissions)
Selden and Song (1994)
6 241
Cole et al. (1997)
9 900
Dissolved oxygen
Grossman and Krueger (1995)
2 703
Fecal coliform
Grossman and Krueger (1995)
7 955
Lead (concentration)
Grossman and Krueger (1995)
1 887
Mercury (concentration)
Grossman and Krueger (1995)
5 047
Nickel (concentration)
Grossman and Krueger (1995)
4 113
Nitrates (concentration)
Grossman and Krueger (1995)
10 524
Cole et al. (1997)
25 000
NO
x
(emissions)
Selden and Song (1994)
12 041
Cole (2003)
14 810
SPM (ambient concentration)
Shafik (1994)
3 280
Grossman and Krueger (1995)
6 151
SPM (emissions)
Selden and Song (1994)
9 811
Cole et al. (1997)
7 300
SO
2
(ambient concentration)
Shafik (1994)
3 670
Grossman and Krueger (1995)
4 053
SO
2
(emissions)
Selden and Song (1994)
8 916
Cole (2003)
8 691
Stern and Common (2001)
18 039
(non-OECD only)
Total coliform
Grossman and Krueger (1995)
3 043
Source:
Cole and Neumayer (2005), p. 310.
insigni
cant, then we get pattern C. These are indicators that show an unambiguous dete-
rioration as incomes increase. These include per capita CO2 emissions. It is possible that
these indicators will follow the EKC pattern but at much higher per capita income turning
points that no countries have yet reached (Neumayer, 2003b, p. 84). The pattern most
often encountered is B, which follows if
fi
is positive and statistically signi
fi
cant and
is
negative and statistically signi
cant. In this case, the estimated EKC has a maximum
turning point per capita income level, calculated as
Y
* = (
fi
). Table 3.1, taken from
Cole and Neumayer (2005), provides the estimated turning points from a large number of
EKC studies. Examples include suspended particulate matter, sulfur dioxide, carbon
monoxide and nitrogen oxide emissions, fecal and total coliforms and the quality of
ambient air (Neumayer, 2003b, pp. 83-4).
A number of caveats should be kept in mind when looking at the results of empirical
studies. For some aspects of the environment, no turning point is in sight. Examples
include CO
2
/2
ows (Seppala et al., 2001,
but see Canas et al., 2003 for contrary evidence) and biodiversity loss (Asafu-Adjaye,
2003).
Econometric evidence captures historical/contemporary evidence. But it is not deter-
emissions, already mentioned, direct material
fl
