Determining Aquatic Bioindicators for Atrazine

1
Determining Aquatic Bio-indicators for Atrazine

• Dr. Andre DeLorme, Valley City State University

2
Introduction

• Long term goal - examine the possible effects of
  atrazine and its metabolites on aquatic
  macroinvertebrates found in streams and rivers in
  North Dakota

3
Background

• A. Atrazine
• Atrazine a triazine herbicide used extensively
  on corn
• In North Dakota 140,000 acres were sprayed with
  Atrazine in 2000
• Majority of this spraying is in the SE corner of
  the state
• Predominantly in the Sheyenne River and Wild Rice
  River watersheds

4
Background

• Atrazine degrades slowly
• This allows it to build up in surface waters such
  as rivers and streams
• Studies done in the early 1990s by the USGS show
  detectable levels of atrazine in the Sheyenne and
  Red River systems
• Both Grand Forks and Fargo use water from the Red
  River system for drinking water purposes

5
Background

• In humans, atrazine is not considered to have
  major carcinogenic or mutagenic properties
• Evidence has been growing that atrazine acts as
  an endocrine disrupter in a wide variety of
  animals

6
Background

• Aquatic Macroinvertebrates are an important part
  of aquatic ecosystems
• Many, especially aquatic insects, undergo drastic
  metamorphic changes that are regulated by
  hormones
• Very little research has been done on the effect
  atrazine may have on hormonally mediated
  developmental changes in insects

7
(No Transcript)
8
Proposal Years 1-3

• 1. Document levels of atrazine contaminants in
  the Sheyenne and Wild Rice rivers in North Dakota
  
• Have been doing water sampling on four sites per
  river for the last 12 months
• Sample once a week during summer months
• Once a month during winter
• Determine atrazine concentrations using ELISA kit
  developed by Abraxis

9
Proposal Years 1-3

• This has been hindered by high water events
• The Wild Rice river was at record highs for most
  of the summer

10
Site E - June 21, 2004
11
Site E July 1, 2005
12
Proposal Years 1-2

• 2. Document possible target macroinvertebrate
  species in the Sheyenne and Wild Rice river
• Currently working with several taxa
• Mayfly larvae from the family Heptageniidae
• Caddisfly larvae from the family Hydropsychidae

13
(No Transcript)
14
Proposal Years 2-3

• 3. Compare contaminate levels with
  macroinvertebrate absence/distribution
  relationships to identify target species for
  specific contaminants
• Do not have consistent enough data to make these
  correlations yet

15
Proposal Years 3-5

• 4. Conduct exposure experiments to determine
  dose/response relationships
• Set up a system of artificial streams to conduct
  exposure tests
• These streams are controlled environments where
  we can vary the atrazine concentrations
• We will look at the effects of atrazine on
  metamorphosis and other hormonally controlled
  physiological functions
• Example see if atrazine influences emergence
  periods of aquatic insects

16
(No Transcript)
17
Proposal

• 5. Future avenues
• Examine physiological effects of atrazine and
  determine the mechanism at a cellular level
• Are there mechanistic correlations?
• Similarities in human and insect endocrine
  activities that are affected by atrazine

18
The project described was supported by NIH Grant
Number P20 RR016741 from the INBRE Program of the
National Center for Research Resources.