Cure #1 in Brine for Brisket
Your question is ...did I use too much cure1...which is sodium nitrate? I dont think there is a safe and not safe limit for this..the more, the less healthy, but there is no poisoning within large margins...

Wikipedia:

Health concerns

Studies have shown a link between increased levels of nitrates and increased deaths from certain diseases including Alzheimer's, diabetes mellitus and Parkinson's, possibly through the damaging effect of nitrosamines on DNA, however, little is done to control for other possible causes in the epidemiological results.[10] Nitrosamines, formed in cured meats containing sodium nitrate and nitrite, have been linked to gastric cancer and oesophageal cancer.[11] Sodium nitrate and nitrite are associated with a higher risk of colorectal cancer.[12] World Cancer Research Fund UK,[13] states that one of the reasons that processed meat increases the risk of colon cancer is its content of nitrate. A small amount of the nitrate added to meat as a preservative breaks down into nitrite, in addition to any nitrite that may also be added. The nitrite then reacts with protein-rich foods (such as meat) to produce NOCs (nitroso compounds). NOCs can be formed either when meat is cured or in the body as meat is digested. For most people, the highest dietary source of nitrates is from fruits and vegetables and no studies have conclusively linked nitrates and nitrites to cancer or any other form of diseases. On the contrary, some research has hinted to beneficial properties of nitrites such as lowering blood pressure by slightly expanding arteries. [14] The only reason nitrates and nitrites came under such legal scrutiny is when the US Food and Drug Administration presented a brief report which stated that some adverse effect was observed on mice (“depression of growth”) when their intake of nitrites was up to 90% of daily diet.[15]