Effect of non-tariff measures on international tea trades

Purpose: The purpose of this paper is to analyze the impacts of differences in sanitary and phytosanitary measures as non-tariff measures (NTMs) in the tea trade between importing and exporting countries. With the progress of trade liberalization, there has been a shift of focus to NTMs as alternative or potential trade barriers. Design/methodology/approach: In order to quantify an NTM on tea trade and implement its empirical application, this study designed an index of differences in maximum residue levels (MRLs) for the pesticide endosulfan and introduced it into a gravity trade model. The estimation challenges in the presence of heteroscedasticity and many zero-trade flows are resolved by taking the Heckman and Poisson pseudo-maximum likelihood estimators. Findings: This study found that differences in MRLs, arising from the stricter standards in importing countries lead to a significant decrease in tea trade value. This negative impact of differences in MRLs is found to be slightly less than that of tariffs, implying that in this case, the NTM acts as a policy substitute for import tariffs in the global tea trade. Originality/value: The main contribution of this study is to suggest and quantify the differences in MRLs across countries as a substantial NTM on the global tea trade and provide its empirical application.