Drugs and Personal Care Products Polluting Water (cont.)

In addition, a primary goal of the U.S. EPA's Office of Research and Development is to identify and foster investigation of potential environmental issues/concerns before they become critical ecological or human health problems. Pollution prevention (e.g., source elimination or minimization) is preferable to remediation or restoration to minimize both public cost and human/ecological exposure.

Current Work: Comprehensive list of EPA research about PPCPs

In what quantities are PPCPs used or introduced to the environment?

As a whole, PPCPs are produced and used in large quantities. Personal care products tend to be made in extremely large quantities - thousands of tons per year. But quantities of production or consumption do not correspond with the quantities of PPCPs introduced to the environment. PPCPs manufactured in large quantities may not be found in the environment if they are easily broken down and processed by the human body or degrade quickly. PPCPs made in small quantities could be over represented in the environment, if they are not easily broken down and processed by the human body and make their way into domestic sewers.

What are some major issues with respect to effects?

The effects of PPCPs are different from conventional pollutants. Drugs are purposefully designed to interact with cellular receptors at low concentrations and to elicit specific biological effects. Unintended adverse effects can also occur from interaction with non-target receptors.

Environmental toxicology focuses on acute effects of exposure rather than chronic effects.

• Effects on aquatic life are a major concern. Exposure risks for aquatic organisms are much larger than those for humans. Aquatic organisms have:
   
  • continual exposures
    
    
  • multi-generational exposures
    
    
  • exposure to higher concentrations of PPCPs in untreated water
    
    
  • possible low dose effects

  
  

• Effects may be subtle because PPCPs in the environment occur at low concentrations. There's a need to develop tests that detect more subtle end-points. Neurobehavioral effects and inhibition of efflux pumps are two examples. Subtle effects that accumulate may be significant.
  
  
• There are little aquatic/terrestrial toxicology data for PPCPs. There is substantially more data available for pesticides. For example, brief exposure of salmon to 1 ppb of the insecticide diazinon is known to affect signaling pathways (via olfactory disruption), leading to alteration in homing behavior (with obvious implications for predation, feeding, and mating). There's concern that low doses of PPCPs may also have effects.
  
  
• There are many drug classes of concern:
   
  • Antibiotics which are actively being researched
    
    
  • Antimicrobials
    
    
  • Astrogenic steroids
    
    
  • Antidepressants. Profound effects on spawning and other behaviors in shellfish can occur with antidepressant selective serotonin reuptake inhibitors (SSRIs).
    
    
  • Calcium-channel blockers. Dramatic inhibition of sperm activity in certain aquatic organisms can be effected by calcium-channel blockers.
    
    
  • Antiepileptic drugs (e.g., phenytoin, valproate, carbamazepine) have potential as human neuroteratogens, triggering extensive apoptosis in the developing brain, leading to neurodegeneration.
    
    
  • Multi-drug transporters (efflux pumps). Possible significance of efflux pump inhibitors (EPIs) in compromising aquatic health.
    
    
  • Musk fragrances are bioaccumulative and persistent
    
    
  • Genotoxic drugs (primarily used at hospitals)

How can I contact scientists working on this topic?

Contact information for research scientists with active research about PPCPs in the environment and government scientists with interest in regulatory aspects, is available. Listing of research scientists and their contact information.

SOURCE: http://epa.gov/ppcp/faq.html

Last Editorial Review: 3/11/2008