Are pumpkins poisonous

Pumpkins aren't poisonous. But, firstly, they are in the cucumber family. A characteristic of that family is toxic levels of nitrate in foliage from too high levels of nitrogen in the soil. Such levels are linked with overfertilizing. And, secondly, pumpkin parts may pick up residue if the grower is chemically controlling weeds. So it is important to respect the wait times between spraying and harvesting/seeding/transplanting, as listed on labels. And it is important to guard against drift.