Parents have the right to understand what is being put into their child’s body. The production of vaccines uses many disgusting ingredients. Additionally, the components used during the manufacturing process may violate your personal, religious, or ethical beliefs.
Lastly, remember that whatever colorful language is used by the scientific community (using such words as purified), using such substances can come with an enormous cost.
As you read this list, understand cell lines and vaccines do become contaminated. This is often hidden under the term “adventitious agents.”
Disgusting Ingredient #1: Cells From Aborted Fetus
Aborted fetal cells, listed on vaccine package inserts as “Human Fetal Diploid Cells.” Two aborted fetal cell lines, WI-38 and MRC-5, have been grown under laboratory conditions since the 1960s.
The cells are used to grow viruses used which are then collected from the cell cultures and processed further to produce the vaccine itself.
Terms to Investigate: PERC6, MRC5, WI-38, HEK-293
Which Vaccines? Adenovirus vaccine, DTaP vaccine, Hep A vaccine, Hep B vaccine, MMR vaccine, Rabies vaccine, Varicella (Chickenpox) vaccine
Disgusting Ingredient #2: Serum From Aborted Calf Fetus Blood
One of the more grotesque methods involved in vaccine manufacturing is the collection of fetal bovine serum. The purpose for serum is providing a nutrient broth for viruses to grow in cells.
How is the blood collected?
According to the Humane Research Australia website:
“After slaughter and bleeding of the cow at an abattoir, the mother’s uterus containing the calf fetus is removed during the evisceration process (removal of the mother’s internal organs) and transferred to the blood collection room. A needle is then inserted between the fetus’s ribs directly into its heart and the blood is vacuumed into a sterile collection bag. This process is aimed at minimizing the risk of contamination of the serum with micro-organisms from the fetus and its environment. Only fetuses over the age of three months are used otherwise the heart is considered too small to puncture.
Once collected, the blood is allowed to clot at room temperature and the serum separated through a process known as refrigerated centrifugation.” 
Terms to Investigate: Fetal Bovine Serum
Which Vaccines? Adenovirus vaccine, MMR vaccine, Rotavirus vaccine, Varicella (Chickenpox) vaccine
Disgusting Ingredient #3: Cells From Armyworms
The FDA approved the Flublok vaccine on January 16, 2013.
This new technology is being touted as the wave of the future. It utilizes an insect cell line (expresSF+®) that is derived from cells of the fall armyworm, Spodoptera frugiperda.
The vaccine package insert for Flublok also mentions:
“Each 0.5 mL dose of Flublok may also contain residual amounts of baculovirus and host cell proteins (≤ 28.5 mcg), baculovirus and cellular DNA (≤ 10 ng) …” 
Terms to Investigate: insect cell line (expresSF+)
Which Vaccines? Influenza vaccine