The Interface between economic development, health and environment in India: An econometric investigation

This paper analyses interrelationships between `economic development', `health', and `environment' in a simultaneous equations framework. Four structural equations have been postulated to explain changes in four endogenous variables in terms of several predetermined variables. The endogenous variables chosen for the model are GDPPC (per capita gross domestic product), LE (life expectancy), NOCRD (number of cases of respiratory diseases) and PM10 (respirable suspended particulate matter). We assume that GDPPC describes economic development prominently and, therefore, use it as one of the endogenous variables in lieu of economic development. LE and NOCRD are assumed to reflect health effects in the economy, and PM10 is used as a proxy of environmental stress. The four endogenous variables are supposed to be jointly determined in terms of several exogenous variables represented through indices of physical infrastructure (PI), social infrastructure (SI) and air pollution index (API). We construct the three indices by the principal components method and thus effectively use only these three predetermined (exogenous) variables to simultaneously determine changes in the four endogenous variables listed above. The model is postulated in loglinear form and estimated by the two-stage least-squares method using data from the Indian economy 1980-81 to 2004-05. It follows from the estimated structural equations that while physical infrastructure is significant in determining GDPPC, the GDPPC is also directly influenced by improved health outcomes like longevity (LE) and lower morbidity from respiratory diseases (NOCRD). The long term health outcome (LE) is determined by the level of per capita GDP and it is positively affected by social infrastructure. The third structural equation shows that the immediate, or short run, health outcomes like morbidity from respiratory disorders are influenced by environmental stress (PM10) besides the level of GDPPC. Finally, the environmental stress (PM10) is determined by the level of per capita GDP and the air pollution index (API) representing various sources of air pollution. It is true that our simplified model illustrates the effects of specific type of air pollutant, viz., respirable particulate matter, however, it is among the most significant environmental problems threatening human health in India. Nevertheless, there is scope to build more comprehensive environmental stress indices which reflect surface water quality, ground water quality, soil pollution etc. which have feedback effects with health and economic development. Also many of the components of PI, SI and API may not be truly exogenous in a larger model (e.g. transport and communication in PI, education and health care systems in SI, and industrial production, vehicular traffic, urbanisation in API.) The two weaknesses of our model stem from data limitation and a concern to simplify the model. Although our model is highly simplified, nonetheless, it provides key insights into the nature of economic development in India during the last 25 years: First, the environmental stress has had a high cost on income and health . from the derived reduced form, a 1 percent increase in the air pollution index leads to a decrease of about 8 percent in the per capita income, a decrease of about 0.7 percent in the life expectancy, and an increase of about 19 percent in the number of cases of respiratory diseases. Second, the social infrastructure plays a more vital role in economic development, health, and environment than the physical infrastructure, since the absolute values of elasticities of endogenous variables with respect to SI are invariably greater than those with respect to PI. Although physical infrastructure is important for economic development, it comes in the last of our preference order. In the final run-up, there is need to pay more attention to provide better social infrastructure and to reduce air pollution.