infrastructures determines the benefits enjoyed by the host community including patronage, loyalties, jobs, contracts, scholarships, social facilities, and compensation (Folami, 2017). The rents from oil and gas companies to communities and the ethnic divide promotes a strong attachment to land in this area. A second contribution of our study is to consider offshore gas flaring. Most evidence on health impacts of flaring is from land-based settings, reflecting a preponderance of studies of fracking. While a large literature considers environmental impacts of offshore oil and gas production (see Wiese et al., 2001 for an early study), little is known about impacts of offshore gas flaring on human health. Yet half of all of Nigeria’s flaring is offshore, with three-quarters of these flaring locations located within 60 km of areas where people live. Evidence has shown that the type of pollutants generated by flaring can affect air quality up to 108 miles (174km) away (Mauzerall, et al., 2005) so it is likely that that offshore flaring has an impact on coastal communities. The examination of the health impact of offshore flaring also has important policy implications in Nigeria where there is a longstanding debate about the distribution of the gains from offshore oil exploration (Egede, 2005). Finally, our study demonstrates the value that can be added to geo-referenced survey data by linking to satellite observations of environmental phenomena, especially for countries that lack the wherewithal for conventional monitoring (Gibson and McKenzie, 2007; Donaldson and Storeygard, 2016).

The rest of the paper proceeds as follows: Section 2 describes some related literature examining gas flaring and human health, Section 3 describes the data and our method of linking satellite-detected gas flaring locations and estimates of gas flared volumes with human health data from DHS. Section 4 contains our results and Section 5 concludes.

# 2. Related literature

A large literature relates air pollution to a host of negative health outcomes (see Manisalidis et al., 2020 for a review). However, identifying causal impacts of air pollution is complicated due to the presence of many confounding factors. Air pollution is not randomly assigned, so unobserved factors may be correlated with both air pollution and health outcomes. People may undertake endogenous risk-avoidance behaviours such that richer people or those who place greater weight on health sort into locations with better air quality so observational data may overstate effects of pollution (Neidell, 2009; Moretti & Neidell, 2011; Sun et al., 2017). Conversely, polluting industries, such as oil and gas, may attract younger, healthier in-migrants in search of employment, so observational studies of polluted areas may underestimate the effects of air pollution. It is also difficult to assign pollution exposure to individuals, so measurement errors may bias estimates of the impact of pollution on health. Notwithstanding these identification difficulties, there is causal evidence that air pollution increases child hospitalisations for respiratory problems (Neidell, 2004; Tzivian, 2011), increases infant mortality (Currie and Neidell, 2005; Knittel, et al., 2016), affects birth outcomes (Currie et al, 2009; 4