ABSTRACT
Nitrogen. (N). and. phosphorus. (P). pollution,. pathogens,. and. odor. of. manure. discharging. from.CAFOs.have.been.a.great.concern. for. several.decades.57,72,113. In. recent.years,.hormones. (estrogens,.androgens,.progesterone,.and.various.synthetic. hormones). contained. in. the. manure. from. CAFOs. have. generated. wide. interest. because.of. their. endocrine.disrupting.effects.48,79,90.When.manure. is. land.applied,. part.of.these.hormones.may.enter.water.systems.through.runoff.or.leaching.24,37,63,102.
and.may.cause.developmental.and.reproductive.impairment.in.aquatic.animals..The. effective.levels.of.these.hormones.may.be.as.low.as.nanograms.per.liter.of.water.17.A. high.incidence.of.intersexuality.(feminization).was.observed.in.a.wide.population.of. male.roaches.in.the.United.Kingdom.64.After.exposure.to.cattle.feedlot.effluent,.both. testosterone.synthesis.and.testis.size.decreased.in.male.fathead.minnows.105
