Original sentence: Research has indicated that teratogens (similar to x-rays), trypan blue (a stain used to color dead tissues or cells blue), and arsenic may damage the developing fetus and cause encephaloceles
Edited sentence: Research has indicated that teratogens (substances known to cause birth defects), trypan blue (a stain used to color dead tissues or cells blue), and arsenic may damage the developing fetus and cause encephaloceles