CBC's I-Team tackles a wide variety of stories in any given year. There are hidden camera shoots, accountability interviews, court cases, long hours on the phone with tipsters who want to remain anonymous, dozens upon dozens of freedom of information requests, and data-mining on all manner of topics.

This year, the investigative team tackled everything from health and safety issues in the nail salon industry to doctors who faced disciplinary action. While we couldn't fit all of our favourite stories in this top 10 list, we managed to cram it with some of the stories we think had an impact in 2016.

Bad malathion

old malathion

The City of Winnipeg fogged with 13-year-old malathion it bought second-hand from the province of Saskatchewan. (Saskatchewan government photo)

It started quite by accident.

I-Team producer Vera-Lynn Kubinec was researching Health Canada's regulatory information for malathion and came across a small but vital change.

It stated that the insecticide should be stored no longer than one year. The longer malathion sits, the more likely it is to produce a more harmful toxin known as isomalathion.

The problem was, Winnipeg's malathion stock was old — some batches dating back 13 years. After being contacted by the I-Team, the city suspended all spraying and started working with Health Canada to get its stockpile of anti-mosquito chemicals tested.

The batch of malathion from 2009 passed lab testing. Health Canada allowed the city to fog again.

However, the batch from 2007 contained excessive isomalathion levels which, according to the lab report, meant the toxicity could be two to four times the level of the World Health Organization's guidelines.

As for the much older 2003 batch of malathion that was used throughout the city in June — we'll never know what it contained. There was none of that batch left when the city realized the problem, and it was never tested for isomalathion.

Open automobile recalls

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Sure, we already knew roughly one in six cars in Manitoba has an open recall. We did that story in 2015.

But this year, we expanded our investigation and found the number holds true nationwide.

That means millions of cars in Canada have unfixed safety issues with things like brakes, steering, seatbelts and airbags.

Changes are coming at the federal level to give the transport minister more power to order recalls and testing on problem parts. But the solution, of course, doesn't just lie in tougher federal legislation.

Industry and industry watchdogs agree the provinces need to help catch open recalls at registration. Not a single province looks for open recalls when it rubber stamps a car for the road.

We'll be watching out for new federal legislation in 2017.

Panama Papers: Donny Lalonde

Lalonde Katie

'Golden Boy' Donny Lalonde talks to the I-Team's Katie Nicholson in St. Julian's, Malta. The boxer's name emerged in the team's look at the Panama Papers. (CBC)

Before the public knew the so-called "Panama Papers" existed, investigative journalists around the world had spent months digging through them, looking for names and connections of notable heads of state, leaders of business and the occasional celebrity.

One name popped out at us — Donny Lalonde, known as "the Golden Boy."

The Panama Papers revealed the charming Canadian boxer appeared to be involved in a complex tangle of real estate companies and developments in Costa Rica that had stalled. It didn't take long to find angry investors who were lining up to sue the Golden Boy for the hundreds of thousands of dollars they say they lost on a dream that never materialized.

​We partnered with the Toronto Star and caught up with Lalonde in Malta, where he insisted he didn't have anything to do with the the Costa Rican developments anymore. The money, he told us, was all tied up in the projects which would still go ahead at some point.

Cormier and Mr. Big

Cormier

Raymond Cormier appears in a Winnipeg court in November 2016. The man accused of killing Tina Fontaine told the I-Team police fabricated evidence against him. (Tom Andrich)

There was a palpable sigh of relief in December 2015, when Winnipeg Police announced they had made an arrest in the death of Tina Fontaine. The teen's death had renewed calls for an inquiry into missing and murdered Indigenous women.

But who was this man charged with her death? And how did police catch him?

Raymond Cormier invited us to the Brandon Correctional Centre to hear his side of the story. He told us he was ensnared in an elaborate "Mr. Big" sting and police fabricated evidence against him.

In a Mr. Big operation, police create a fictitious criminal organization and invite the target to join, in an effort to gather more evidence and secure a confession.

Cormier admits he knew Fontaine, but insists police have the wrong man. He has even filed a Law Enforcement Review Agency complaint against police.

Expect more answers in May of 2017 when a preliminary hearing is slated to begin.

Not-quite-all-in pricing

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It was a simple concept: the price you see is the price you pay.

When Manitoba's Consumer Protection Office ushered in the new truth-in-advertising legislation for car dealerships in June 2015, there was much fanfare. Under the new regulations, car dealerships couldn't tack on extra fees to the advertised price of a car.

But when we put that to the test more than a year later, we found seven out of 10 dealerships we visited tried to add extra fees to the advertised price.

​Since the story aired, the CPO began investigating dozens of complaints.

Father Ron Léger charged again

Ron Leger sits with guard

Father Ron Léger sits in a Winnipeg court in November and listens to the details of the new charges against him. A guard sits next to him. (Tom Andrich)

Father Ron Léger was probably hoping the worst was behind him.

In 2015, the Roman Catholic priest pleaded guilty to three counts of sexual assault. But just weeks after being granted day parole in September, Winnipeg police picked him up again.

Four more men have come forward alleging they, too, were sexually abused by Léger. They shared their disturbing accounts of abuse, which they say began when they attended a youth drop-in centre Léger allegedly used like a spider web to catch young victims.

Unresolved: Investigating MMIW

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Partnering with the CBC Indigenous Unit and our CBC colleagues across Canada, we took a closer look at 34 cases involving the deaths or disappearances of Indigenous women in which foul play had been ruled out.

The families of the women didn't agree with those assessments, and as our investigations unfolded we found more unanswered questions.

In fact, the one thing these cases seemed to have in common was that they all begged for more in-depth investigation.

Locally, the I-Team took a closer look at the case of Rocelyn Gabriel, who was was found nearly frozen to death outside the Portage la Prairie recycling depot in 2014. Gabriel died hours later in a Winnipeg hospital.

Her sister Olivia is still looking for answers, and believes someone brought her to the depot that night and left her there.

Lead in Brandon water

Brandon water

An investigation found the amount of lead in 10 per cent of water samples from Brandon exceeded safe levels. (Lyzaville Sale CBC)

Brandon has struggled with elevated levels of lead in its water for a few years now, but it had taken steps to combat the problem.

But when the I-Team tested 30 random samples of tap water in Brandon homes in February, it found 10 per cent of the samples exceeded safe lead levels, even after a five-minute flush.

After the I-Team's story, the city council agreed to help subsidize home filtration systems for affected homeowners until it has flushed its lead problem for good.

Retailers sell restricted pesticides

round up

Secret shoppers were able to buy Roundup for cosmetic purposes at six out of nine stores back in May. (CBC News Graphics)

Manitoba cracked down on the use of cosmetic pesticides with legislation that came into effect in 2015. But did retailers follow suit?

Our hidden camera investigation revealed retailers routinely flouted the rules governing the sale of cosmetic pesticides. Six out of the nine stores we visited sold our secret shopper the product in contravention of the legislation.

After our investigation, the retailers told us they were re-educating staff about the law and how the products could be sold. Under the legislation, Roundup can be sold for use on noxious weeds like poison ivy, but not for harmless weeds like dandelions.

Woman declared dead, says she isn't

Alyanna Lapuz and Nicholson

Alyanna Lapuz shows the I-Team's Katie Nicholson the documents that say she is dead. (CBC News)

Alyanna Lapuz was hale and hearty and about to go to school in Toronto when she learned she was dead … according to the taxman, anyway.

What started as a slightly amusing situation quickly became a major frustration and financial problem for the student.

​Dead girls don't get student loans, and her enrolment in a dental hygienist program was in jeopardy.

For weeks, Lapuz got the runaround from the Canada Revenue Agency. But the very day the I-Team told her story, the agency brought her back to life.