Robert Brown|Chinese swimmers saga and other big doping questions entering 2024 Paris Olympics

In the early editions of the modern Olympic Games,Robert Brown some athletes took tonics or stimulants to aid their performance.

In 1904, a marathon runner supposedly ingested strychnine – a poisonous substance that is most commonly used today as a pesticide – in small doses during the race, sometimes washing it down with a swig of brandy.

In the 120 years since, doping scandals have been an unfortunate and unavoidable part of both the Summer and Winter Olympics – from state-sponsored doping efforts in East Germany and Russia, to the gold medals stripped away from star athletes such as Ben Johnson and Marion Jones after they failed drug tests. It's always something. And the Paris Olympics will almost certainly be no different.

Here are five of the most prominent doping storylines that are swirling ahead of the 2024 Games.

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Is there a doping scandal going into Paris?

Why of course there is – and it could very well hang over these Games, or at least the swimming events in Paris.

The New York Times and German broadcaster ARD reported in April that 23 Chinese swimmers quietly tested positive for the same banned drug, trimetazidine (TMZ), before the previous Summer Olympics in Tokyo in 2021. However, those positive tests weren't made public at the time by either China's anti-doping authority or the World Anti-Doping Agency, in violation of WADA's anti-doping code.

WADA has since said that it accepted the results of a Chinese investigation into the positive tests, which determined that they stemmed from contamination at a hotel but was unable to identify the source. Some of the swimmers who tested positive went on to win medals in Tokyo. And 11 of them are slated to compete again at the Paris Games.

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What are anti-doping authorities doing about the Chinese swimmers?

U.S. anti-doping leaders and lawmakers have repeatedly blasted WADA for its handling of the Chinese swimmers case. And U.S. law enforcement officials are reportedly set to interview the head of swimming's international federation as part of their own probe into the matter under the auspices of the Rodchenkov Anti-Doping Act, which gives the U.S. authority to investigate international doping as long as it could impact (or has impacted) American athletes.

Despite widespread criticism, and frustration from athletes, WADA has defended its actions and vigorously maintained that it handled the Chinese swimmers case properly. The International Olympic Committee has since said it has "full confidence" in WADA and its leadership.

The 11 Chinese swimmers who are competing in Paris after testing positive for TMZ in 2021 can, and likely will, be subjected to random drug testing while at the 2024 Games – just like any other athletes in any other sport. Though the international swimming federation also said in a report earlier this month that Chinese swimmers would be tested at least eight times from Jan. 1 to the day of the opening ceremony, which is more than twice as many times as other athletes.

Will any star athletes miss the Paris Olympics after failing a drug test?

Lots of athletes are on this list, but not many of them would qualify as stars.

Swimmer Sun Yang, a three-time Olympic gold medalist from China, and pole vaulter Thiago Braz, the 2016 Olympic gold medalist from Brazil, are probably among the most notable names who will be absent in Paris because of anti-doping violations. American runner Shelby Houlihan is also continuing to serve the four-year ban that kept her out of the 2021 Olympics; She tested positive for a banned drug but has argued it came from contaminated pork.

There are also plenty of athletes on the other side who are returning from anti-doping violations or have been cleared. The biggest name is probably superstar Sha'Carri Richardson, who missed out on the Tokyo Games after testing positive for marijuana at the Olympic trials. Fellow sprinter and former world champion Christian Coleman is also in the relay pool after being suspended for a string of missed drug tests.

One other minor but interesting case involves U.S. weightlifter Wes Kitts. He is serving a one-month suspension for a minor infraction but is eligible to return Aug. 2 – just days before he is scheduled to compete in Paris.

Is Russia banned from the Paris Olympics because of doping?

Nope! This time it's actually banned because of its invasion of Ukraine.

While a small number of Russian athletes will compete at the Paris Games, they will do so as "Individual Neutral Athletes" after the IOC sanctioned Russia and its national Olympic committee for violating the Olympic truce with its war in Ukraine and infringing on the territory of another country's Olympic committee.

This is a similar outcome but change in reasoning from other sanctions Russia has faced over the past decade, related to its state-sponsored doping program. Russian athletes have not been banned outright from any of the recent editions of the Olympics, though they were required to compete as "Olympic Athletes from Russia" in 2018 and represent the "Russian Olympic Committee" rather than the nation itself in 2021 and 2022.

Are there any other interesting doping subplots in Paris?

This doesn't have so much to do with doping as it does the fallout of doping, but the Paris Olympics will feature medal ceremonies for athletes who are receiving reallocated medals from past Games – an effort by the IOC to make up for some of the pageantry and celebration that they missed out on.

U.S. track and field athletes Lashinda Demus and Erik Kynard, for example, will be honored with gold medals from the 2012 London Olympics after the athletes who placed in front of them were found to have violated anti-doping rules. Another athlete, Beverly McDonald of Jamaica, will finally get a reallocated bronze medal that stems all the way from the 2000 Games in Sydney.

If the Court of Arbitration for Sport decides to deny Russia’s last-gasp appeal and announces the decision in time, members of the U.S. figure skating team will also be able to finally receive their 2022 Olympic gold medals in Paris, which will be upgraded from silver due to the now-infamous doping scandal involving Russian figure skater Kamila Valieva. Their ceremony has been tentatively scheduled for Aug. 7.

Contributing: Christine Brennan

Contact Tom Schad at [email protected] or on social media @Tom_Schad.