A plumber had came to my house to sweat pipes to install a water valve which controlled water going to the garden spigot. Upstream to the valve is a t-joint. The other output to the t-joint went to the kitchen faucet. Now, he suggested to me that if the water line to the garden spigot on the output end of the t-joint contained lead solder or lead pipes, it would not contaminate the flow of water going to the kitchen. Instead, all of the water-contaminated lead will be used to water the grass.
Is this true??