The bins are overflowing in large areas of Paris a week into a strike by waste collectors, with thousands of tonnes of rubbish sitting abandoned on the streets of the French capital.
"It's dirty, it attracts rats and cockroaches," one Parisian complained on French radio.
The workers are striking over the Macron government's proposals to raise the pension age from 62 to 64.
Other cities including Nantes, Rennes and Le Havre are also affected.
Refuse collectors joined the pension strikes a week ago and the Paris authority says half of the city's districts, which are covered by council workers, have been hit by the action. Three waste treatment sites have been blockaded and a fourth partially closed.
On Monday, the Paris authority said 5,600 tonnes of waste had yet to be collected.
One commentator on Europe1 radio described the situation as an all-you-can-eat buffet for the six million rats of Paris, double the human population.
In the 10 districts covered by private companies the service was running almost normally, Paris council said. Some reports indicated activists were trying to prevent collections from going ahead.
And one private company was also seen on Monday night by news channel BFMTV picking up waste in one of the big central districts, the sixth, which is normally covered by council workers.
Similar bin collections were going on in two other districts on the western fringe of the city.
Leading council official Emmanuel Grégoire said the situation was complicated but the authority was prioritising intervention for public safety, with a focus on clearing food markets, bin bags lying on the ground and ensuring pedestrian safety.
"The strike triggers a change in rat behaviour," specialist Romain Lasseur told Le Parisien newspaper. "They'll rummage around in bins, reproduce there, and leave their urine and droppings. We have a worrying health risk for refuse collectors and the general population."
The capital's bin workers are due to meet on Wednesday to decide whether to continue their action.
Refuse collectors currently retire at the age of 57 because of difficult working conditions and under the reforms they would have to work for two more years.
Opponents of the Socialist mayor of Paris have seized on the strike as only adding to an existing crisis.
"Anne Hidalgo promised to double the clean-up budget and Parisians clearly see Paris becoming dirtier and dirtier," complained Rachida Dati who runs the seventh district for the right-wing Republicans.
France's unions have stepped up action against the government's unpopular retirement reforms which are currently going through parliament.
Several operators at French refineries were on strike on Tuesday for a seventh day in a row, but only a small proportion of French petrol stations have had to close.
The measures were backed by the upper house or Senate on Saturday and will next go to a joint committee of MPs from both houses on Wednesday to decide on the final text. A final vote could reach the National Assembly and Senate on Thursday.
President Emmanuel Macron's party lacks a majority in the lower house so victory on the bill is by no means secure.
The government needs 287 votes, and even if it can persuade all its 250 MPs to back the reforms it will still need to find another 37 lawmakers from other parties to back the higher pension age.
Many of those extra votes are likely to be Republicans and the government is keen to avoid pushing through the measures without triggering a 49:3 article of the constitution, which enables ministers to force through legislation without a vote.