Spring
2016
Grains
West
36
Feature
F YOU DON’T KNOWWHAT
MRL stands for, you can be
forgiven. Maximum residue
limits have been, until recently, not
something that most grain farmers in
Western Canada have had on their radar.
If you bought registered crop protection
products and used them according to
the label, all was well.
That’s not entirely accurate, of course.
Whether you knew it or not, establishing
and monitoring global MRLs has been an
ongoing process since the 1960s. In the
absence of a problem, it’s not something
many farmers would have had to worry
about. In 2011, however, MRL issues
following glyphosate use on pulse crops
destined for Europe brought the issue
to the fore. Then, in 2015, the lack of
an MRL in the U.S. for the plant growth
regulator Manipulator prompted grain
buyers to refuse grain delivery and ask
for declarations of use.
Can these trade disruptions be
avoided? To a degree, yes, but MRL
setting and management is a complex,
global issue. It’s important to first
understand how the MRL regulatory
system works.
HOWMRLS ARE SET
Each and every crop protection product
registered in Canada is subject to an
MRL—an allowable amount, in parts per
million, of residue on the harvested grain
or oilseed.
I
In Canada, once a new crop
protection product is created, the crop
protection company submits reams of
data to the Pest Management Regulatory
Agency (PMRA) in support of product
registration. The PMRA then not only
assesses the product’s crop safety and
other parameters, but also its safety to
human health. “Health Canada must
determine whether the consumption
of the maximum amount of residues,
that are expected to remain on food
products when a pesticide is used
according to label directions, will not be
a concern to human health,” reads the
PMRA website.
Countries around the world can
establish their own MRLs through
BY LYNDSEY SMITH • PHOTOS COURTESY OF JOHN DEERE CANADA AND THE CANADIAN GRAIN COMMISSION
KNOW YOUR
LIMITS
