The regulatory landscape around genetically modified crops has largely been shaped by public opinion and historical context. Not by economics. European resistance to GM crops, for example, was influenced by the contemporaneous mad cow disease crisis and slow regulatory procedures that allowed public opposition to build. 

Many nations, including India with the sole exception of cotton, have adopted similar bans. Most of the opposition does not stem from intrinsic risks or inefficiency, but from pressure to maintain export access to European markets.

More generally, non-governmental organizations and activists have repeatedly raised public health, environmental, and ethical concerns about growing and consuming GM crops with great success. As a result, only 29 nations today authorise the commercial cultivation of GM crops. An additional 42 nations permit the import of GM crops but not commercial cultivation. This, despite the fact that the scientific community considers GM crops to be beneficial in net to the environment. 

So, do we lose something from these bans?

To answer this question, it is helpful to look at cotton, maize, rapeseed, and soybeans, that together account for 98% global GM crop production and divide the world into two regions–one in which GM crops are authorised and another in which GM crops are banned. New research does just this and employs econometric techniques to investigate the economic impacts of GM crops globally. Specifically, this research leverages the variation in the timing and types of GM crop approvals across nations and crops to identify causal effects on yields, land use, and trade.

It was found that GM crops significantly increase agricultural yields, particularly in lower-income, warmer nations. These regions suffer more from pests and weeds—issues that GM crops are specifically engineered to mitigate. For instance, in India, if GM maize were allowed then yields could increase by as much as 64%. Using data from 120 nations over 1986 to 2019, this research found that GM cotton yields increased by about 4.6% annually over 10 years post-approval, with smaller gains observed for maize. Rapeseed and soybeans showed modest impacts on yield and this is most likely because their cultivation spread to less suitable lands.

What about land use changes? Such changes were minimal for most crops, indicating that higher yields do not generally come at the expense of expanded cropland. One exception is soybeans, whose cultivation did expand after GM adoption. However, this expansion is heavily influenced by global demand, particularly from China, which prefers importing soy over cereals due to tariff differences and dietary shifts. Interestingly, the research showed that GM technologies may have given South American producers a competitive edge in supplying this Chinese demand stemming from cultivation bans in China.

A fundamental point emphasised by the research was the unrealised global potential of GM crops. In 2019, GM technology raised global agricultural output by $39 billion and saved 3.4% of global cropland which is roughly the size of Spain. That said, it is salient to comprehend that this represents only one-third of the potential impact, as bans on GM crop cultivation in many countries, especially in Sub-Saharan Africa and the European Union, have curtailed broader adoption. If bans on the cultivation of GM crops had been lifted a decade earlier, global agricultural output in 2019 would have been $69 billion higher.

Finally, consider the environmental benefits from GM crops. Specifically, the decreased conversion of natural land to cultivate crops checks both losses in biological diversity and greenhouse gas emissions. In this regard, some scholars have pointed out that if Europe were to adopt GM crops, then this would reduce emissions by 33 million tons per year. In fact, the research demonstrates that the potential for reducing emissions this way is even greater in developing countries, where the yield advantage of GM crops is larger. So, even though some concerns about the environmental impacts of GM crops remain, the research strengthens the present scientific consensus that GM crops are, in net terms, beneficial for the environment.  

(Views expressed are personal)