Assessing the effects of Irgarol 1051 on marine phytoplankton populations in Key Largo Harbor, Florida

Mar Pollut Bull. 2006 Aug;52(8):935-41. doi: 10.1016/j.marpolbul.2005.12.010. Epub 2006 Feb 10.


The antifouling boosting agent Irgarol 1051 is a strong inhibitor of the photosystem II (PSII) with high efficiency/toxicity towards algae. However, because some phytoplankton species are more sensitive to Irgarol than others, its persistent release into the environment could result in adverse changes in the phytoplankton community structure at heavily impacted sites such as marinas. Continuous monitoring in the Florida Keys showed Irgarol concentrations of up to 635 ngL(-1) in the canal system leading to Key Largo Harbor Marina (KLH) with a sharp decrease in concentration at stations offshore from the mouth of the canal. Preliminary phytoplankton community assessments from surface water samples collected in KLH between February and August 2004 showed changes in several phytoplankton species in concordance with the increase of the herbicide concentrations. Typical responses include an increase in the abundance of eukaryotes and Cryptomonas sp. as Irgarol concentrations increase.

Publication types

  • Comparative Study

MeSH terms

  • Chlorophyll / analysis
  • Dose-Response Relationship, Drug
  • Ecosystem
  • Florida
  • Flow Cytometry
  • Herbicides / pharmacology*
  • Phytoplankton / chemistry
  • Phytoplankton / classification
  • Phytoplankton / drug effects*
  • Phytoplankton / isolation & purification
  • Population Density
  • Seasons
  • Seawater / analysis
  • Time Factors
  • Triazines / analysis
  • Triazines / pharmacology*
  • Water Pollutants, Chemical / analysis
  • Water Pollutants, Chemical / pharmacology*


  • Herbicides
  • Triazines
  • Water Pollutants, Chemical
  • Chlorophyll
  • irgarol 1051