2017 US EPA Integrated Science Assessment – Sulphur Dioxide
In December 2017, the US EPA published an updated integrated science assessment for sulphur dioxide using research published to end August 2016. Key findings on causality are summarised below as compared with the 2008 assessment.
The assessment also noted that reproductive and developmental effects were inadequate to infer a causal relationship for a wide range of exposure durations.
It should be noted that the assessment did not consider transformation products such as sulfate (these being considered in the integrated science assessment for particulate matter, US EPA, 2009).
Full assessment here:
Table 1. Causal determinations: short-term exposure*
| Health effect category | 2008 SOx ISA | 2017 SOx ISA |
| Respiratory effects | Causal relationship | Causal relationship |
| Cardiovascular effects | Inadequate to infer a causal relationship | Inadequate to infer a causal relationship |
| Total mortality | Suggestive of, but not sufficient to infer a causal relationship | Suggestive of, but not sufficient to infer a causal relationship |
*Short-term exposure refers to time periods of minutes up to 1 month
Table 2. Causal determinations: long-term exposure**
| Health effect category | 2008 SOx ISA | 2017 SOx ISA |
| Respiratory effects | Inadequate to infer a causal relationship | Suggestive of, but not sufficient to infer a causal relationship |
| Cardiovascular effects | Not included | Inadequate to infer a causal relationship |
| Total mortality | Inadequate to infer a causal relationship | Inadequate to infer a causal relationship |
| Cancer | Inadequate to infer a causal relationship | Inadequate to infer a causal relationship |
*Long-term exposure refers to time periods of more than one month to year.