Arthur, a 7-year-old boy from Brazil’s Paraná region tragically lost his life after playing in limestone dust and posing for an innocent family photo.

The deadly incident occurred on August 3, in the town of Ipriranga, southern Brazil.

7-year-old Arthur was playing on the side of the road under the watchful eye of his family when he noticed a pile of fine white dust. The boy apparently thought it would be fun to roll and play in it and even cover himself in the white dust like kids usually do with sand, at the beach.

His parents apparently didn’t see anything wrong with it either, and they even took a photo of the boy playing and posing with two thumbs up.

They had no idea that this would be the last photo of the young boy alive. Moments after getting up from the pile of white dust, Arthur started feeling bad and he was taken to a local hospital, but doctors could do nothing to save his life.

What Arthur and his family didn’t know was that the pile of dust that some construction company had allegedly dumped on the side of the road was actually limestone dust.

A common concrete filler, it can cause irritation to the skin and the eyes in the case of direct contact, but it is particularly dangerous when inhaled.

Although Arthur only played in the dust for a few minutes, he reportedly inhaled quite a bit of it, which proved fatal.

Limestone dust contains silica crystals, which, when inhaled, can cause serious diseases like lung cancer, COPD, and silicosis. T

he latter is the result of accumulated silica particles in the lungs which causes inflammation and scarring.

However, silicosis usually occurs after years of exposure to breathable silica.

According to Brazil’s Institute for Research and Technology, if a person inhales limestone dust and starts exhibiting poisoning symptoms, they should receive artificial respiration or oxygen and immediate medical attention.

Unfortunately, Arthur’s family had no idea what he was exposing himself to. They posted the boy’s last photo both as a tribute to him, and as a warning for other parents not to repeat their mistake.