title: The biotic ligand model: a historical overview.
abstract: During recent years, the biotic ligand model (BLM) has been proposed as a tool to evaluate quantitatively the manner in which water chemistry affects the speciation and biological availability of metals in aquatic systems. This is an important consideration because it is the bioavailability and bioreactivity of metals that control their potential to cause adverse effects. The BLM approach has gained widespread interest amongst the scientific, regulated and regulatory communities because of its potential for use in developing water quality criteria (WQC) and in performing aquatic risk assessments for metals. Specifically, the BLM does this in a way that considers the important influences of site-specific water quality. This journal issue includes papers that describe recent advances with regard to the development of the BLM approach. Here, the current status of the BLM development effort is described in the context of the longer-term history of advances in the understanding of metal interactions in the environment upon which the BLM is based. Early developments in the aquatic chemistry of metals, the physiology of aquatic organisms and aquatic toxicology are reviewed first, and the degree to which each of these disciplines influenced the development of water quality regulations is discussed. The early scientific advances that took place in each of these fields were not well coordinated, making it difficult for regulatory authorities to take full advantage of the potential utility of what had been learned. However, this has now changed, with the BLM serving as a useful interface amongst these scientific disciplines, and within the regulatory arena as well. The more recent events that have led to the present situation are reviewed, and consideration is given to some of the future needs and developments related to the BLM that are envisioned. The research results that are described in the papers found in this journal issue represent a distinct milestone in the ongoing evolution of the BLM approach and, more generally, of approaches to performing ecological assessments for metals in aquatic systems. These papers also establish a benchmark to which future scientific and regulatory developments can be compared. Finally, they demonstrate the importance and usefulness of the concept of bioavailability and of evaluative tools such as the BLM.
authors.affiliation: HydroQual Inc, Mahwah, NJ 07403, USA. ppaquin@hydroqual.com
authors.forename: Paul R
authors.initials: PR
authors.lastname: Paquin
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Gorsuch
authors.forename: Simon
authors.initials: S
authors.lastname: Apte
authors.forename: Graeme E
authors.initials: GE
authors.lastname: Batley
authors.forename: Karl C
authors.initials: KC
authors.lastname: Bowles
authors.forename: Peter G C
authors.initials: PG
authors.lastname: Campbell
authors.forename: Charles G
authors.initials: CG
authors.lastname: Delos
authors.forename: Dominic M
authors.initials: DM
authors.lastname: Di Toro
authors.forename: Robert L
authors.initials: RL
authors.lastname: Dwyer
authors.forename: Fernando
authors.initials: F
authors.lastname: Galvez
authors.forename: Robert W
authors.initials: RW
authors.lastname: Gensemer
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Goss
authors.forename: Christer
authors.initials: C
authors.lastname: Hostrand
authors.forename: Colin R
authors.initials: CR
authors.lastname: Janssen
authors.forename: James C
authors.initials: JC
authors.lastname: McGeer
authors.forename: Rami B
authors.initials: RB
authors.lastname: Naddy
authors.forename: Richard C
authors.initials: RC
authors.lastname: Playle
authors.forename: Robert C
authors.initials: RC
authors.lastname: Santore
authors.forename: Uwe
authors.initials: U
authors.lastname: Schneider
authors.forename: William A
authors.initials: WA
authors.lastname: Stubblefield
authors.forename: Chris M
authors.initials: CM
authors.lastname: Wood
authors.forename: Kuen Benjamin
authors.initials: KB
authors.lastname: Wu
mesh_terms: D000818:Animals; D004784:Environmental Monitoring / Q000379:methods*; D005399:Fishes / Q000378:metabolism / Q000502:physiology; D006801:Humans; D008024:Ligands; D008670:Metals / Q000378:metabolism / Q000633:toxicity; D008954:Models, Biological; D014873:Water Pollutants / Q000378:metabolism / Q000633:toxicity
chemical_list: D008024:Ligands; D008670:Metals; D014873:Water Pollutants