You're in luck! There are three recent/soon to be published books that IAIA members have edited or contributed to:
Health Impact Assessment: Past Achievement, Current Understanding, and Future Progress -John Kemm
Health Impact Assessment: Principles and Practice - Martin Birley
Health Impact Assessment: Past Achievement, Current Understanding, and Future Progress -John Kemm
Health Impact Assessment: Principles and Practice - Martin Birley
In the unlikely event that they don't want any of these Croakey has published a collection of health-related reading suggestions.