In a decision released this week, the Racing Integrity Board said the offending was serious.
"It not only undermines the integrity of the racing industry but poses a serious animal welfare and safety issue," it said.
"This is not a situation of 'one-off' use of the drug. He has admitted using methamphetamine on a regular basis for the past year."
The board also noted that Toomer should have been especially aware of the risks of methamphetamine contamination and dogs.
"Less than 2 years ago his father, a former Greyhound trainer, was disqualified from training because another sibling ... contaminated one of his greyhounds, on the very same property that the Respondent now uses to kennel his greyhounds.
"It is simply inconceivable that the Respondent would not have been aware of the risks associated with his use of the drug methamphetamine."
The board said the case must serve as a severe warning to others in the industry who may contemplate using prohibited drugs while they have greyhounds in their care.
"Thankfully, the detection of methamphetamine is a relatively rare occurrence within racing. But a concern is the emerging risk of cross-contamination. An increasing number of positives have emerged," it said.
One of those cases of cross-contamination was in April this year when Whanganui horse trainer Rochelle Lockett and her horse both tested positive for meth.
In that case, Lockett admitted smoking meth in the days prior to the race in which her horse Be Flexi finished first.
Since 2001 there have been 14 cases where trainers or jockeys have tested positive for methamphetamine.
The first instance of a horse testing positive for the drug was I'm Not Ticklish in 2014. Its trainer Tracey Newton was banned for three years and denied giving her horse meth, nor did she have any of it in her system.