Dividend growth streaks are impressive, but investors should be careful not to assume that they will continue indefinitely. Changes can happen with a company and new risks may arise, potentially putting once-safe dividend payments in jeopardy. Three stocks with impressive growth streaks that I could see ending before the end of the decade are Johnson & Johnson (JNJ -0.46%), Altria Group (MO -0.37%), and 3M (MMM 0.46%).

1. Johnson & Johnson

In April of this year, healthcare giant Johnson & Johnson announced it would be raising its dividend by 5.3%. It marked the 61st consecutive year that the company has increased its payout. It's a long streak, even among other Dividend Kings. 

Its 3.3% dividend yield is attractive right now, but this is not a payout that I would feel comfortable buying and forgetting about. That's because the company still faces the risk of paying out substantial fines for the talc-related lawsuits brought against it. With tens of thousands of plaintiffs and multiple judges now rejecting the company's efforts to put the liabilities in a subsidiary and to bankrupt it, in an effort to cap its potential exposure to the claims, there's a huge cloud over the business.

This isn't something investors can simply brush off by saying that Johnson & Johnson makes billions, so it can easily absorb that risk. That simply isn't true -- not when one of the settlements involved $2.1 billion in damages to just 22 women who said they contracted ovarian cancer because of the company's talc products.

Earlier this year, the company proposed a $12 billion settlement over the course of 25 years (estimated present value of $8.9 billion) to address the claims. That suggests that Johnson & Johnson knows that the legal costs could be much more significant than that, otherwise it wouldn't go to such lengths. It also limited its liability further by spinning off its consumer health business into Kenvue. While it will indemnify the company for liabilities that arise in North America and Canada, Kenvue will be on the hook for lawsuits that originate in other countries.

These talc lawsuits could have a devastating effect on the company's financials, and on the dividend. It could take years to determine how this will all play out and what kind of bill Johnson & Johnson ends up with. And that is why there is a decent chance the company's dividend streak may come to an end before this decade ends. Risk-averse investors are better off going with other dividend stocks instead.

2. Altria Group

Tobacco maker Altria Group has an impressive dividend streak that involves increasing its payout 58 times in a span of 54 years. And at 9.8%, it also offers an enormous dividend yield right now. Normally, a high yield wouldn't last that long, not even for a Dividend King with an impressive track record.

In Altria's case, the problem is its core business. Net revenue of $6.3 billion was down 4% for the period ending Sept. 30. Cigarette smoking rates have been falling for decades. Less than 14% of adults smoked as of 2018, down from more than 42% in 1965, according to the American Lung Association.

The company has tried pivoting to other growth opportunities, including investing in vaping company Juul, but that simply hasn't panned out. Altria faces an uncertain future, and its dividend already looks to be on shaky ground.

Last quarter, it reported a diluted per-share profit of $1.22. If it were to maintain that level of profitability, its payout ratio would be approximately 80%. While that's still sustainable for the time being, it isn't a terribly low payout ratio, either. And it may be difficult for Altria to continue raising its dividend if its financials don't improve.

As tempting as this dividend stock may be, there's a real risk that the company will stop raising its payouts in the near future. While it can still provide you with a good yield, this is far from a risk-free investment.

3. 3M

3M is a large conglomerate with a presence in many industries. But despite that diversification, this too could be a risky dividend stock to be holding. It is facing potentially billions in legal fees, and its financials aren't looking as strong as they used to be. The company has, however, potentially put to rest one risk, involving its earplugs. It recently reached a settlement worth approximately $6 billion.

It also has a tentative settlement involving forever chemicals and U.S. public water systems that will cost $10.3 billion. However, not all states are on board with the deal, which could result in a higher cost for 3M. Some analysts believe that in the end, 3M may need to take on $30 billion in debt just to take care of all the lawsuits it's facing.

Things aren't looking great for 3M. The company reported net revenue of $8.3 billion in its most recent quarter, for the period ending Sept. 30. That was a decline of 3.6% year over year. 3M's planning to spin off its healthcare business later this year (which accounts for one-quarter of its top line), and that will also affect the company's financials.

3M is facing an uncertain future. While it has increased its dividend for 64 consecutive years, investors shouldn't assume that the streak is safe. Its 6.9% dividend yield looks attractive, but investors should be aware of the risks involved with the stock. 3M isn't the safe investment it was a few years ago, and it may not be suitable for risk-averse investors.