# **5 Potential Health Impacts**

The results in Section 3 show a large decline in the food-fish catch as riverine salinity moves from its minimum to maximum level during the year. A decline of this magnitude has potentially serious health implications for the region, since ample previous research has documented the role of fish protein intake in promoting mother/child health in Bangladesh (Rifata et al. 2023; Andrews et al. 2022; Dasgupta et al. 2021; Dasgupta and Wheeler 2019; Ferdous et al. 2015; Bogard et al. 2015). As Figure 3 and our econometric results show, the decline of food fish supplies is concentrated during the period of rapid riverine salinity increase in the spring. The magnitude of the associated health impacts depends upon whether mothers have the resources to compensate for declining fish supplies by increasing consumption of other protein sources. In this context, Bangladesh’s recent progress in reducing poverty is notable. According to the World Bank’s World Development Indicators, the country’s multidimensional poverty headcount ratio was 31.3% in 2010, 20.5% in 2016 and 6.6% in 2022. While the southwest coastal area remains relatively poor when compared with other regions, it has undoubtedly benefited from this trend.

Under current conditions, are the resources of poor households adequate to compensate for the sharp salinity-induced swings in riverine fish supplies in the southwest coastal region? To address this question, we have extracted the relevant individual and household data from the two most recent Bangladesh Demographic and Health Surveys (DHS): 2022 and 2018. We have limited our sample to household clusters in the six southwest coastal districts that are most strongly impacted by salinity-driven fluctuation in fish supplies. The two most recent DHS surveys do not include survey information for the peak salinity months, so we cannot draw direct inferences from the data. However, they do include information about the birth months of surveyed children. This permits investigation of differences in child morbidity and mortality measures for children born during the three peak salinity months (March, April, May) when food fish stocks are sharply lower.

Table 3 reports our results for DHS sampling clusters in southwest coastal Bangladesh during the survey years 2018 and 2022. Sample sizes for the two years are 1,271 and 1,344 individuals. The table reports means and percent differences for probabilities of mortality, diarrhea and stunting for children born in peak salinity months and off-peak months.<sup>2</sup>

**Table 3:  Southwest coastal Bangladesh – peak salinity at birth and child morbidity/mortality**<sup>**3**</sup>

|||Peak<br>Salinity<br>|||||||
|---|---|---|---|---|---|---|---|---|
|N|Year|Birth<br>Month|Prob.<br>Death|%<br>Difference|Prob.<br>Diarrhea|%<br>Difference|Prob.<br>Stunted|%<br>Difference|
|1,271|2018|0|0.039||0.037||0.258||
||2018|1|0.048|25.187|0.062|69.896|0.280|8.787|
|1,344|2022|0|0.025||0.048||0.100||
||2022|1|0.028|13.333|0.040|-16.478|0.127|26.543|

> 2 We use the conventional definition of moderate to severe stunting, which corresponds to a height-for-age z-score below -2.0.

> 3 The probability of death in Table 3 is the incidence of children reported dead for whom birth months are provided.

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