Alpha particles are helium nuclei that have a +2 charge. They attract electrons from the environment in order to stabilize charge. The result is a complete helium atom. Beta particles are either free electrons or their anti-particles, positrons. Gamma rays are electromagnetic radiation similar to X-rays, only more energetic. There is also neutrino emission. Neutrinos have a non-zero but extremely small mass, are electrically neutral and in general do not interact with regular matter to any appreciable extent. Neutrinos are mentioned in domains of nuclear chemistry only because mass-energy balances of many radioactive processes would be incomplete without them.
Alpha particles have little effect on the environment in terms of propagating radioactive properties. The two electrons obtained from surroundings would of course alter local electronic structure from which they were obtained. If an alpha source is concentrated, surrounding molecular structure may be a bit different than usual due to alpha particles' repeated electron "stealing" from nearby molecules. Beta radiation is also harmless unless a beta-radiation source is ingested. Gamma rays are the most difficult to stop. Thick lead or concrete is required. Their effect is similar to that of X-rays, so gamma ray sources are considered cancer-causing hazards. Neutrinos hardly interact at all, so have no effect on environments people encounter.
Nuclear chemistry theory is the foundation of MRI medical imaging. By systematically exciting hydrogen nuclei in the body with magnetic fields, the protons "jump" to a higher energy state. As the nuclei return back to lower energy by emitting radio waves, a real-time map of virtually any body part can be obtained without incisions or injections. Nuclear chemistry is also essential for understanding and using nuclear power. To harness atomic energy safely, cadmium rods are dispersed throughout the reactor, absorbing neutrons that propagate the chain reaction among uranium atoms. Cadmium rods serve as a rate moderator that can control the speed--and therefore energy output--of a nuclear fission generator. Georgia State University has an excellent article titled "Control Rods for Fission Reactors" that expands on this overview.