Be careful since I can't find a lot of official sources saying this is not a dangerous plant.
"The seeds of purslane are so powerful they can stay viable in land for up to 40 years – and this is a natural crop – no GMO! It grows in a well-tended garden and in arid climates, often equally as well. This resilient plant poses similar benefits for our immune systems and overall health.
Often called pig weed (and it certainly would be better for your pigs than some of the GMO grain many farmers have been using to feed their livestock), Purslane has more beneficial Omega 3 fatty acids than many fish oils! The weed also has one of the highest levels of vitamin A among all leafy green vegetables (1320 IU/100 g, provides 44% of RDA). High Vitamin A foods can help protect us from many types of cancers and helps to boost eye health.
Furthermore, purslane is full of two different types of betalain alkaloid pigments – a reddish beta-cyanis and a yellow beta-xanthins, which are equally potent antioxidants and anti-mutagens. Also in purslane are vitamins C, and B-complex including riboflavin, pyridoxine, and niacin, as well as carotenoids, and trace minerals like iron, magnesium, and calcium"
See entire article @ EatLocalGrown