A new study in rats found that Roundup altered testicular function after only 8 days of exposure at a concentration of only 0.5%, similar to levels found in water after agricultural spraying, writes Claire Robinson.
The study found no difference in sperm concentration, viability and mobility, but there was an increase in abnormal sperm formation measured 2, 3, and 4 months after this short exposure.
The study, the first to measure the delayed effects of exposure to Roundup on sperm in mammals from a short exposure, was conducted by a team including Prof Gilles-Eric Séralini at the University of Caen, France.
Roundup was found to change gene expression in sperm cells, which could alter the balance of the sex hormones androgen and estrogen. A negative impact on sperm quality was confirmed, raising questions about impaired sperm efficiency. The authors suggested that repeated exposures to Roundup at doses lower than those used in agriculture could damage mammalian reproduction over the long term.
The study's findings should raise alarm in farm workers, as well as people who spray Roundup for municipal authorities and even home gardeners. People exposed to lower doses repeated over the long term, including consumers who eat food produced with Roundup and people who happen to be exposed to others' spraying activities, should also be concerned.
Those who want to conceive a child should take special measures to minimise their exposure, including eating organic food and lobbying for a ban on Roundup spraying in their neighbourhoods.
An acute exposure to glyphosate-based herbicide alters aromatase levels in testis and sperm nuclear quality
Estelle Cassault-Meyer, Steeve Gress, Gilles-Éric Séralini, Isabelle Galeraud-Denis
Environmental Toxicology and Pharmacology
Volume 38, Issue 1, July 2014, pp. 131–140
- We investigated the effects of a glyphosate-based herbicide after an 8-day exposure of adult rats.
- We have shown a significant and differential expression of aromatase in testis.
- We have observed a diminution of mRNA expression of nuclear markers in spermatozoa.
- These results suggest changes in androgen/estrogen balance and in sperm nuclear quality.
- The repetition of exposures of this herbicide could alter the mammalian reproduction.
Roundup is the major pesticide used in agriculture worldwide; it is a glyphosate-based herbicide. Its molecular effects are studied following an acute exposure (0.5%) of fifteen 60-day-old male rats during an 8-day period. Endocrine (aromatase, estrogen and androgen receptors, Gper1 in testicular and sperm mRNAs) and testicular functions (organ weights, sperm parameters and expression of the blood–testis barrier markers) were monitored at days 68, 87, and 122 after treatment, spermiogenesis and spermatogenesis. The major disruption is an increase of aromatase mRNA levels at least by 50% in treated rats at all times, as well as the aromatase protein. We have also shown a similar increase of Gper1 expression at day 122 and a light modification of BTB markers. A rise of abnormal sperm morphology and a decrease of the expression of protamine 1 and histone 1 testicular in epididymal sperm are observed despite a normal sperm concentration and motility.